AU650573B2 - Timber connecting apparatus - Google Patents

Description

6 7 Regutation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

TO BE COWLE=E BY APPLICANT Name of Applicant: ERIC ALEXANDER BREW and PHILLIP JOHN BREW Actual Inventors: ERIC ALEXANDER BREW; PHILLIP JOHN BREW Address for Service: CALLINAN LAWRIE, 278 High Street, Kew, 3101, Victoria, Australia invention Title: "TIMBER CONNECTING APPARATUS" The following statement is a full des.cription rof this invention, including the best method performing it known to us:- -2- TIMBER CONNECTING APPARATUS This invention relates to timber connecting apparatus, particularly for connecting timber pieces in a desired relationship such as prefabricated roof truss manufacture.

Australian Paten it Specification No. 62,323/73 discloses an apparatus by which timber pieces can be connected end to end by a machine to which nail plates are fed. The nail plates are indexed by rotary platens into a desired position and the platens are then moved towards each other to embed the projections of the nail plates into the timber pieces located between the platens. This particular apparatus is designed for joining timber pieces end to end only and in particular is not suitable for joining timber pieces in variable relationships such as prefabricating roof trusses.

The present method of prefabricating roof trusses generally comprises laying out timber pieces on a jig. When the different pieces in are their desired position they are clamped and nail plates are manually applied to the timber pieces at the connection regions. Australian Patent Specification No. 26,973/77 discloses an apparatus for prefabricating roof trusses in which nail plates can be applied to the connection regions by means of a press have platens which are movable towards each other to apply nail plates to the timber connection regions. The 5 press is suspended from an overhead assembly. The nail plates nfumA be manually located in position prior to operation of the press.

It is an object of the present invention to provide a timber co'n-ecting apparatus for use in connecting timber pieces together and in which nail plates can -3be fed automatically into their required positions.

It is a further object of the present invention in a first aspect to provide a timber connecting apparatus in which two nail plates can be fed automatically into a clamp for application to opposite sides of the timber pieces in their connection region.

It is a further preferred object of the present invention according to a secoid aspect to provide a timber connecting apparatus for use in connecting timber pieces together in which nail plates are fed automatically into a clamp preparatory to movement of the clamp into an operative position before a clamping operation.

It is a further preferred object of the present invention according to a third aspect to provide a timber connecting apparatus in which timber pieces can be supported and located in variable relationships so that the apparatus can be readily used in manufacturing timber articles having timber pieces in different arrangements.

SAccording to the present invention in a first aspect there is provided a timber connecting apparatus for use in connecting timber pieces together, the apparatus including: supporting and locating means for supporting and locating timber pieces in their desired relationship before connection together; a clamp for '25 location at the general region where the timber pieces are to be connected together, the clamp including a pair of clamp jaws which are relatively movable towards and away from each other with the timber pieces to be connected together being located between the clamp jaws; and a nail plate feed for feeding nail plates -4to the damp jaws, the nail plates having projections whicl, are embedded in the timber pieces when the clamp jaws move towards each other, the nail plate feed being arranged to feed to the clamp jaws two nail plates with the projections of each nail plate being directed towards the other nail plate so that each one of the nail plates is associated with a respective clamp jaw when the jaws are separated.

The damp is preferably movable between an advanced position in which it is located for use in connecting the timber pieces together and a retracted position in which the clamp is removed from the general region where the timber pieces are to be connected together so as to enable locating of timber pieces to be connected and removal of pieces after connection. Preferably one damp jaw is fixed with reference to the damp. More preferably the damp jaws are disposed vertically with respect to each other, the upper damp jaw being fixed.

The nail plate feed may comprise a magazine in which a number of pairs of facing nail plates can be located, a first such pair of nail plates being presented by the magazine for feeding of that pair to the damp jaws, the nail plate feed including a feeder operatively associated with the magazine and operative to feed the first pair of nail plates from the magazine into the damp jaws.

Preferably, means operated by compressed air is used to push the pair of nail plates into the clamp jaws.

'2D Preferably the magazine is arranged to hold a stack of pairs of nail plates, each pair of nail plates comprising two nail plates having the projections of each nail plate being directed towards the other nail plate, the magazine being of adjustable cross-sectional area so that different sized nail plates can be stacked in the magazine at different times with the nail plates being fed to the damp jaws in known positions and orientations.

The magazine may be mounted on or to the damp adjacent to the jaws displaced in the general direction from the advanced position of the clamp towards the retracted position of the damp, the feeder comprising a pusher, operated by compressed air, which is operative to push the first pair of nail plates from the magazine into the jaws, preferably as the damp is moved away from its advanced position towards its retracted position. Alternatively the magazine may be releasably mountable within a recess provided in the damp.

In the preferred arrangement the clamp jaws are located one above the other, the lower of the two clamp jaws comprising an anvil on which a lower one of the two nail plates fed to the clamp jaws rests, the upper damp jaw having an associated holding means for holding the upper one of the nail plates so that the upper nail plate can be held elevated above the lower nail plate and spaced therefrom to receive the timber pieces betweei, the nail plates.

In this embodiment the holding means (which may include magnets) may comprise two edge holding members arranged to contact and hold opposite edges of the upper nail plate, the edge holding members being relatively movable apart so as to receive the upper nail plate therebetween and being biased towards one another by biasing means so as to grip and hold the upper plate by the action of the biasing means. One of the edge holding members may comprise a vertically movable holding member which is mounted by the upper clamp jaw and is capable of lifting to allow the upper nail plate to be moved laterally into its pos;ition -6associated with the upper clamp jaw, the other edge holding member comprising an abutment against which the upper nail plate bears, the vertically movable holding member being capable of moving downwardly behind an edge of the upper nail plate and holding the upper nail plate between the abutment and the vertically movable holding member.

Preferably the damp jaws are relatively close together when the two nail plates are fed into the space between the two dclamp jaws so that the holding means associated with the upper clamp jaw cooperates with the upper one of the two nail plates fed into the dclamp jaws after which, separation of the two dclamp jaws enables the two nail plates to separate with the upper nail plate being held by the upper jaw and the lower nail plate resting on the lower jaw. Restraining means may be used to prevent or limit undesirable movement of the lower nail plate with respect to the lower jaw. These may comprise magnets embedded in Sthe upper face of the lower jaw.

According to the present invention in a second aspect, which may be used in conjunction with the first aspect, there is provided a timber connecting apparatus for use in connecting timber pieces together, the apparatus including: S, supporting and locating means for supporting and locating timber pieces in their desired relationship before connection together; a clamp for location at the general 0 region where the timber pieces are to be connected together, the damp includ ing a pair of damp jaws which are relatively moveable towards and away from each other with the timber pieces to be connected together being located between the damp jaws; and a nail plate feed for feeding nail plates to the clamp jaws, the nail -7plates having projections which are embedded in the timber pieces when the clamp jaws move towards each other; the clamp being selectively movable between an advanced position in which it is located for use in connecting the timber pieces together and a retracted position in which the clamp is removed from the general region where the timber pieces are to be connected together so as to enable locating of timber pieces to be connected and removal of pieces after connection; the nail plate feed comprising a magazine in which a number of pairs of facing nail plates can be located, a first such pair of nail plates being presented by the magazine for feeding of that pair to the clamp jaws, the nail plate feed including a feeder operatively associated with the magazine and operative to feed the first pair of nail plates from the magazines into the clamp jaws.

Preferably the clamp jaws are disposed vertically with respect to one another, the upper clamp jaw being fixed with reference to the clamp.

According to the present invention in a third aspect which may be used in conjunction with the first and/or second aspects, there is provided a timber connecting apparatus for use in connecting timber pieces together, the apparatus including: supporting and locating means for supporting and locating the timber pieces in their desired relationship before connection together, the supporting and locating means comprising at least two support means for supporting and locating "2"D the timber pieces at least in the vicinity of the regions where the timber pieces are to be connected together, a locating track arrangement along which the support means are movable to enable selective variation of the locations of the support means; a clamp for location at the general region where the timber pieces are to -8be connected together, the clamp including a pair of clamp jaws which are relatively movable towards and away from each other with the timber pieces to be connected together being located between the clamp jaws; and a nail plate feed for feeding nail plates to the clamp jaws, the nail plates having projections which are embedded in the timber pieces when the clamp jaws move towards each other, the nail plate feed being arranged to feed to the clamp jaws two nail plates with the projections of each nail plate being directed towards the other nail plate so that each one of the nail plates is associated with a respective clamp jaw when the jaws are separated.

Preferably the locating track arrangement includes at least two tracks arranged at an angle to each other, the angle between the tracks being selectively variable so as to enable the support means to be located for use with timber pieces to be arranged at different angles to each other.

In the preferred embodiment the locating track arrangement includes a base track extending generally along the desired line of a bottom chord of a roof truss to be assembled in the apparatus and two rafter tracks extending at an angle to the base track, the rafter tracks meeting at an apex, the base and rafter tracks each having associated support means movable along at least part of the, length thereof so that timber pieces can be arranged to form a roof truss having the "2D general shape defined by the arrangement of the base and rafter tracks. Preferably the intersection of at least one of the rafter tracks with the line of the base track is selectively movable lengthwise of the base track so as to enable selective variation of the length of the bearer of the truss being manufactured.

-9- At least one of the tracks may be telescopically movable so as to enable selective variation of the length of the track for enabling different lengths of timber to be supported by the support means movable on that track.

The two rafter tracks may be pivotally movable relative to each other at the apex where they meet so as to enable associated timber pieces defining the rafters of a roof truss, to be arranged at selected different angles to each other.

The timber connecting apparatus may include a clamp associated with each support means, each clamp being movable between an advanced position in which it is located for use in connecting the timber pieces together and a retracted position located out of the general line of the associated track, the clamp in its retracted position being displaced from the general region where the timber pieces are to be connected together so as to enable locating of timIber pieces to be connected and removal of the pieces after connection.

The timber connecting apparatus may further include control means for enabling operator control of the location of the support means in relation to the locating track arrangement, the control means including drive means for driving the support means along the track arrangement, the drive means being selectively S operable so as to enable location from a central control location of the support means at their desired positions. The control means preferably includes a %t.O programmable controller operative to determine the positions for the support means for a particular arrangement of timber pieces to be connected, the programmable controller being further operadive to control the operation of the drive means so as to control the movement and final locations of the support means.

Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the invention.

In the drawings: Fig. 1 is a schematic plan view of a timber roof truss manufacturing arrangement; Fig. 2 is a schematic plan view of a supporting and locating means for use in manufacture of timber trusses; Fig. 3 is an exploded perspective view of a clamp usable in the apparatus of the present invention; Fig. 4 is an exploded perspective view of the upper jaw of a clamp usable in the present invention; Fig. 5 is a section through the upper jaw of Fig. 4; Fig. 6 is a schematic section through a clamp usable in the apparatus of the present invention showing the clamp prior to the insertion of a pair of nail plates; Fig. 7 is a schematic: section through the clamp of Fig. 6 showing the 20 clamp at the time a pair of nail plates are inserted into the damp just prior to separation of the damp jaws; Fig. 8 is a schematic section through another clamp usable in the apparatus of the present invention after separation of the clamp jaws following 11 insertion of a pair of nail plates; and Fig. 9 is a schematic view of a nail feed mechanism useable in the clamp of Fig. 8.

The timber connecting apparatus according to the preferred embodiment of the present invention is for connecting timber pieces so as to form a roof truss as shown in Fig. 1. The roof truss 10 includes a bottom chord 11 and two rafters 12 meeting at an apex 13 and an arrangement of bracing members 14 for making the structure rigid. The timber pieces making up the roof truss 10 must be connected together at the regions 15 indicated by the dotted circles and this is usually carried out by fixing nail plates or "gang nails" which span the timber pieces meeting at the regions 15, the nail plates having projections pointing from one face in use which are embedded in the timber pieces so as to connect them together. The nail plates are usually fixed to both sides of the timber pieces. The timber pieces need to be supported inl their desired relationship as shown in Fig.

1 during the operation of fixing the nail plates.

The fixing of the nail plates is carried out by clamps 23 which are movable between advanced positions 20 in which the clamps 23 are located for connecting the timber pieces together and retracted positions 20a shown in broken S line in which the clamps 23 are removed from the regions 15 where the timber pieces are to be connected together. This facilitates location of timber pieces to be connected and removal of the pieces, particularly removal of the fabricated roof truss after the connection operation.

The timber connecting apparatus includes supporting and locating -12means 17 which are indicated schematically in Fig. 2 for supporting and locating timber pieces in their desired relationship before connection. The supporting and locating means 17 preferably comprise pedestals on which the timber pieces are supported.

The damps 23 each comprise a pair of clamp jaws 21, 22 which are relatively movable towards and away from each other with the timber pieces to be connected together located between the clamp jaws 21, 22, In this embodiment upper clamp jaw 22 is fixed with reference to the clamp by being welded to the frame of the damp. A nail plate feed 25 is arranged for feeding nail plates 26, 27 to the clamp jaws 21, 22. The nail plates 26, 27 have projections which are embedded in the timber pieces as damp jaw 21 moves towards upper clamp jaw 22 with the timber pieces being located between the clamp jaws. Preferably, the timber pieces are located first against the upper clamp jaw 22 before the lower clamp jaw 21 moves towards the upper clamp jaw 22. This may be achieved by having the clamp 23 move into position against the timber pieces prior to upward S; movement of the lower clamp jaw 21. The nail plate feed 25 is arranged to feed to the damp jaws 21, 22 two nai! plates 26, 27 with projections of each nail plate being directed towards the other nail plate so that each one of the nail plates is associated with a respective clamp jaw 21- 22 when the jaws are separated.

The nail plate feed 25 in Fig. 3 comprises a magazine 29 in which a number of pairs 30 of facing nail plates 26, 27 are located in use, the first such pair of nail plates 26, 27 being presented by the magazine 29 for feeding of that pair to the damp jaws 21, 22. The feed 25 includes a feeder 31 associated with the -13magazine 25 and operative to feed the first pair 30 of the nail plates 26, 27 from the magazine 25 onto the clamp jaws 21, 22 via a pneumatic cylinder, i'his will locate the nail plates 26, 27 in the clamp jaws preparatory to movement of the clamp from its retracted to its advanced position for a subsequent timber connecting operation.

The magazine 29 is arranged to hold a stack of pairs 30 of nail plates 26, 27, each pair 30 of nail plates comprising two nail plates having the projections of each nail plate being directed towards the other nail plate. The magazine is of adjustable cross-section area for example, by means of selectively replaceable inserts 33 which can be located in the magazine so that different sized nail plates 26, 27 can be stacked in the magazine 29 at different times with the nail plates being fed to the clamp jaws 21, 22 in known positions and orientations. As seen in Fig. 3, the magazine 29 is mounted to the clamp 23 adjacent to the jaws 21 and 22, and immediately behind the jaws, i.e. displaced as indicated by the arrow A which indicates the general direction of movement for the clamp 20 moving from its advanced position towards its retracted position. The feeder 31 comprises a pusher 32 which is operative by a pneumatic cylinder 28 to push the first pair of the nail plates 26, 27 from the bottom end of the magazine 29 into the jaws 21, 22 as the clamp 23 is moved away from its advanced position in the direction of arrow A towards its retracted position.

The clamp jaws 21, 22 are located one above the other, the lower jaw 21 comprising an anvil on which the lower nail plate 26 rests, the upper clamp jaw 23 which is fixed having an associated holding means 40 for holding the upper -14plate 27 so that the upper nail plate 27 can be held elevated above the lower nail plate 26 resting on the anvil 21 and spaced therefrom to receive the timber pieces between the nail plates 26, 27. The anvil 24 of the lower jaw 21 is mounted on round plate 33 at the end of rod 34, the position of plate 33 being controlled by means of hydraulic cylinder Referring particularly to Figs. 4, 5, 6, and 7 the holding means comprises two edge holding members 41, 42 arranged to contact and hold opposite edges of the upper nail plate 27. The edge holding members 41, 42 are relatively movable apart so as to receive the upper nail plate 27 therebetween anca are biased towards one another by biasing means 43 so as to grip and hold the upper plate 27 by action of the biasing means 43. The edge holding member 41 comprises a vertically movable holding member 44 illustrated as a pivotally movable finger which is mounted by the upper clamp jaw 22 so that it is capable of lifting as shown in broken line in Fig. 5 to allow the upper nail plate 27 to be moved into its position associated with the upper clamp jaw 22. The edge holding member 42 comrprises an abutment 45 against which the upper nail plate 27 bears. The finger 44 moves downwardly after the nail plate 27 has passed in the direction of arrow B so as to move downwardly behind the trailing edge of the upper nail plate 27 and hold the nail plate 27 between the abutment 45 and the finger 44.

In use, the damp jaws 21, 22 are relatively close together when the two nail plates 26, 27 are fed into the space between the two clamp jaws so that the holding means 40 assodated with the upper clamp jaw 22 co-operates with the upper nail pL, e 27 fed into the clamp jaws, after which separation of the jaws enables the two nail plates 26, 27 to separate with the upper nail plate 27 being held by the upper jaw 22 and the lower nail plate 26 resting on the lower jaw 21.

The abutment 45 in Fig. 4 is in the form of a downwardly extending projection mounted on a sleeve 46, the sleeve 46 being slidable along a rod 47 mounted by the upper jaw 22. The biasing means 43 is shown as a spring which allows the sleeve 46 and the abutment 45 to move away from the holding member 44 when the nail plate 27 is first moved into position in the direction of arrow B.

This will enable the nail plate 27 to be moved past the finger 44 so that the finger can pivot downwardly behind the edge of the nail plate 27 as shown in Fig. 5, the pivoting downwardly of the finger 44 also being under the influence of the biasing means 43. When the clamp advances and the pusher 32 is no ionger bearing against the nail plates, the spring 43 will pull the sleeve 46 and the abutment back and will pull the nail plate 27 back into engagement with the finger 44 so that the nail plate 27 will then be gripped between the finger 44 and the abutment As the lower jaw 21 is separated from the upper jaw 22, the nail plate 27 will be retained by the upper jaw.

Alternatively, as shown in Fig. 8, the nail plates may be magnetically held in position on the clamp jaws. In this clamp, lower clamp jaw 21 is fixed with respect to the clamp 23b and upper clamp jaw 22 is movable by means of a hydraulic press cylinder 36 mounted in the upper part of clamp 23b. The nail feed mechanism 31a comprises a pusher 32 movable by means of pneumatic cylinder 28, the movement of arm 38 on which pusher 32 is mounted being guided by slot 37 in plate 39 part of which forms anvil 24 of bottom jaw 21. In Fig. 9, 30a (in broken -16lines) denotes a nail plate in the position just prior to separation, and 29a (in broken lines) denotes the nail connector plate magazine.

Referring to Fig. 2, the supporting and locating means comprises support means 17 for supporting and locating the timber pieces at least in the vicinity of the regions 15 where the timber pieces are to be joined together. The supporting and locating means also includes a locating track arrangement 50 along which the support means 17 are movable to enable selective variation of the locations of the support means. The locating track arrangement 50 includes a base track 51 extending generally along thee desired line of the bottom chord of the roof truss to be assembled and two rafter tracks 52, 53 meeting at the apex 13. The S base track 51 and rafter tracks 52, 53 each have associated support means 17 movable along at least part of the length thereof so the timber pieces can be arranged to form the roof truss having the general triangular shape defined by the arrangement of the base and rafter tracks 51, 52, 53. The intersection of one or both of the rafter tracks 52, 53 with the base track 51 may be selectively movable lengthwise of the base track 51 as indicated by the arrows C, D so as to enable selective variation of the length of the bottom chord of the truss being manufactured.

Preferably the tracks 51, 52, 53 are telescopically movable so as to enable selective variation of the length of the tracks so that different lengths of timber can be supported by the support means 17 movable on the tracks. The two rafter tracks 52, 53 are pivotally movable relative to each other at the apex 13 so as to enable the rafter tracks 52, 53 to be shortened or lengthened for the same length -17of base track 51 so that the angle between the rafter tracks 52, 53 can be selectively varied.

Associated with each support means 17 there is preferably provided a clamp 55 movable between its advanced operative position and a retracted position located out of the general line of the associated track. As illustrated schematically in Fig. 2, the clamp 55, and the other dclamps not illustrated, may be movable along a clamp track 56 from its operative position shown to its retracted position shown at 55a. The angle of the clamp track 56 to the line of the track 51 may be selectively variable, e.g. as shown at 56a, so that the line of movement of the clamp 55 between its advanced and retracted positions can be selectively varied by the operator for ease of access to the truss or to the whole assembly.

The apparatus may include control means, not illustrated, for enabling operator control of the location of the support means 17 in relation to the track arrangement 50. The control means may include drive means for driving the support means 17 along the track arrangement 50. The drive means may be selectively operable to enable location of the support means 17 at their desired positions, the control being carried out from a central control location. The drive to the support means 17 may be any suitable arrangement and may comprise for

S..

example, screw threaded shafts extending along each of the tracks 51, 52, 53, each support means 17 being engagable with the respective screw threaded shaft by a meshing follower so that the selectively engaging and disengaging the follower, the supports 17 can be moved along the tracks from a remote control location.

Alternatively, the drive to the support means 17 may comprise a fixed chain with -18a sprocket follower driven by a hydraulic or electric motor mounted in the supports 17.

The control means may include a programmable controller operative to determine the positions for the support means 17 for a particular arrangement of timber pieces to be constructed, such as a particular truss arrangement. The programmable controller may be operative to control the operation of the drive means so as to control the movement and locations of the support means 17. In this way the apparatus may be operated from a central location for example, by inputting the desired dimensions of the truss to be manufactured, the programmable controller then being operative to calculate the location of the regions where connections of timber pieces will be required and to automatically move the support means and associated damps to their determined positions by directly configuring the track arrangement 50 and then moving the support means 17 and, associated damps 55 along the tracks. With this arrangement, the apparatus can be used for producing customised trusses in small production runs in an economical manner.

It will be seen that the preferred construction and arrangement of the apparatus according to the present invention as described and illustrated enable the nail plates to be fed automatically to the damps so as to be in position for fixing to both sides of the timber pieces to be connected. The apparatus can be readily reconfigured for different arrangements of timber pieces so that the apparatus can be versatile in operation.

It is to be understood that various alterations, modifications and/or -19additions may be made to the features of the possible and preferred embodiment(s) of the invention as herein described without departing from the spirit and scope of the invention.

Claims (21)

1. A timber connecting apparatus for use in connecting timber pieces together, the apparatus including: supporting and locating means for supporting and locating timber pieces in their desired relationship before connection together; a clamp for location at the general region where the timber pieces are to be connected together, the clamp including a pair of clamp jaws which are relatively movable towards and away from each other with the timber pieces to be connected together being located between the clamp jaws; and a nail plate feed for feeding nail plates to the clamp jaws, the nail plates having projections which are embedded in the timber pieces when the clamp jaws move towards each other, the nail plate feed being arranged to feed to the damp jaws two nail plates with the projections of each nail plate being directed towards the other nail plate so that each one of the nail plate is associated with a respective clamp jaw when the jaws are separated.

2. A timber connecting apparatus as claimed in Claim 1 wherein the clamp is moveable between an advanced position in which it is located for use in connecting the timber pieces together and a retracted position in which the clamp is removed from the general region where the timber pieces are to be connected together so as to enable locating of timber pieces to be connected and removal of pieces after connection.

3. A timber connecting apparatus as claimed in either Claim 1 or Claim 2 wherein one clamp jaw is fixed with reference to the damp.

4. A timber connecting apparatus as claimed in Claim 3 wherein the -21- clamp jaws are disposed vertically with respect to one another, the upper clamp jaw being fixed with reference to the clamp.

A timber connecting apparatus as claimed in any one of Claims 1 to 4 wherein the nail plate feed includes a magazine in which a number of pairs of facing nail plates can be located, a first such pair of nail plates being presented by the magazine for feeding of that pair to the clamp jaws, the nail plate feed including a feeder operatively associated with the magazine and operative to feed the first pair of nail plates from the magazine into the clamp jaws.

6. A timber connecting apparatus as claimed in Claim 5 wherein means operated by compressed air is used to push the pair of nail plates into the clamp jaws.

7. A timber connecting apparatus as claimed in Claim 5 wherein the magazine is arranged to hold a stack of pairs of nail plates, each pair of nail plates comprising two nail plates having the projections of each nail plate being directed towards the other nail plate, the magazine being of adjustable cross-sectional area so that different sized nail plates can be stacked in the magazine at different times with the nail plates being fed to the clamp jaws in known positions and orientations.

8. A timber connecting apparatus as claimed in any one of Claims 1 to 7 wherein the clamp jaws are located one above the other, the lower of the two clamp jaws comprising an anvil on which a lower one of the two nail plates feed to the clamp jaws rests, the upper clamp jaw having an associated holding means for holding the upper one of the nail plates so that the upper nail plate can -22- be held elevated above the lower nail plate and spaced therefrom to receive the timber pieces between the nail plates.

9. A timber connecting apparatus as claimed in Claim 8 wherein the holding means comprises two edge holding members arranged to contact and hold opposite edges of the upper nail plate, the edge holding members being relatively movable apart so as to receive the upper nail plate therebetween and being biased towards one another by biasing means so as to grip and hold the upper nail plate by the action of the biasing means.

A timber connecting apparatus as claimed in Claim 9 wherein one of the edge holding members comprises a vertically movable holding member which is mounted by the upper clamp jaw and is capable of lifting to allow the upper nail plate to be moved laterally into its position associated with the upper damp jaw, the other edge holding member comprising an abutment against w;hich the upper nail plate bears, the vertically movable holding member being capable of moving downwardly behind an edge of the upper nail plate and hold the upper nail pl'te between the abutment and the vertically movable holding member.

11. A timber connecting apparatus as claimed in Claim 10 wherein the clamp jaws are relatively close together when the two nail plates are fed into the space between the two damp jaws so that the holding means associated with the upper damp jaw cooperates with the upper one of the two nail plates fed into the clamp jaws after which, separation of the two clamp jaws enable the two nail plates to separate with the upper nail plate being held by the upper jaw and the lower nail plate resting on the lower jaw. -23-

12. A timber connecting apparatus for use in connecting t.i'nber pieces together, the apparatus including: supporting and locating means for supporting and locating timber pieces in their desired relationship before connection together; a clamp for location at the general region where the timber pieces are to be connected together, the damp including a pair of clamp jaws which are moveable towards and away from each other with the timber pieces to be connected together being located between the clamp jaws; and a nail plate feed for feeding nail plates to the clamp jaws, the nail plates having projections which are embedded in the timber pieces when the clamp jaws move towards each other; the clamp being selectively movable between an advanced position in which it is located for use in connecting the timber pieces together and a retracted position in which the clamp is removed from the general region where the timber pieces are to be connected together so as to enable locating of timber pieces to be connected and removal of pieces after connection; the nail plate feed comprising a magazine in which a numbcr of pairs of facing nail plates can be located, a first such pair of nail plates being presented by the magazine for feeding of that pair to the clamp jaws, the nail plate feed including a feeder operatively associated with the magazine and operative to feed the first pair of nail plates from the magazines into the clamp jaws.

13. A imber connecting apparatus for use in connecting timber pieces together, the apparatus including: supporting and locating means for supporting and locating the timber pieces in their desired relationship before connection together, tl e supporting and locating means comprising at least two -24- support ,means for supporting and locating the timber pieces at least in the vicinity of the regions where the timber pieces are to be connected together, a locating track arrangement along which the support means are movable to enable selective variation of the locations of the support means; a clamp for location at the general region where the timber pieces are to be connected together, the damp including a pair of damp jaws which are relatively movable towards. nd away from each other with the timber pieces to be connected together being located between the damp jaws; and a nail plate feed for feeding nail plates to the damp jaws, the nail plates having projections which are embedded in the timber pieces when the damp jaws move towards each other, the nail plate feed being arranged to feed to the damp jaws two nail plates with the projections of each nail plate being directed towards the other nail plate so that each one of the nail plates is associated with a respective clamp jaw when the jaws are separated.

14. A timber connecting apparatus as claimed in Claim 13 wherein the locating track arrangement the locating track arrangement includes at least two tracks arranged at an angle to each other, the angle between the tracks being selectively variable so as to enable the support means to be located for use with timber pieces to be arranged at different angles to each other.

15, A timber connecting apparatus as claimed in either Claim 13 or Claim 14 wherein the locating track arrangement includes a base track cxtending generally along the desired line of a bottom chord of a roof trass to be assembled in the apparatus and two raft.:r tracks extending at an angle to the base track, the rafter tracks meeting at an apex, the base and rafter tracks each having associated support means movable along at least part of the length thereof so that timber pieces can be arranged to form a roof truss having the general shape defined by the arrangement of the base and rafter tracks.

16. A timber connecting apparatus as claimed in Claim 15 wherein the intersection of at least one of the rafter tracks with the line of the base track is selectively movable length wise on the base track so as to enable selective variation of the length of the bearer of the roof truss being manufactured.

17. A timber connecting apparatus as claimed in Claim 16 wherein at least one of the tracks is telescopically movable so as to enable selective variation of the length of the track for enabling different lengths of timber to be supported by the support means movable on that track.

18. A timber connecting apparatus as claimed in any orn., of Claims 11 to 17, including a damp associated with each support means, each damp being movable between an advanced position in which it is located for use in connecting the timber pieces together and a retracted position located out of the general line of the associated tract, the clamp in its retracted position being displaced from the general region where the timber pieces are to be connected together so as to enable lucating of timber pieces to be connected and removal of the pieces after connection.

19. A timber connecting apparatus as claimed in any one of the preceding claims further including control means for enabling operator control of the location of the support means in relation to the locating tract arrangement, the control means including drive means for driving the support means along the tract -26- arrangement, the drive means being selectively operable so as to enable location from a central control location of the support means at their desired positions.

A timber connecting apparatus as claimed in Claim 19 wherein the control means includes a programmable controller operative to determine the positions for the support means for a particular arrangement of timber pieces to be connected, the programmable controller being further operative to control the operation of the drive means so as to control the movement and final locations of the support means.

21. A timber connecting apparatus as claimed in any one of the preceding claims substantially as hereinbefore described. D A T E D this 28th day of September 1992. ERIC ALEXANDER BREW and PHILLIP JOHN BREW By their Patent Attorneys: CALLINAN LAWRIE 6t et go ABSTRACT A timber connecting apparatus for use in connecting timber pieces together, including supporting and locating means (17) for supporting and locating timber pieces in their desired relationship before connection together, comprising at least two support means for supporting and locating the timber pieces at least in the vicinity of the regions (15) where the timber pieces are to be connected together, and a locating track arrangement along which the support means are movable to enable selective variation of the locations of the support means; a clamp (23) for location at the general region (15) where the timber pieces are to be connected together, including a pair of clamp jaws (22) relatively movable towards and away from each other with the timber pieces to be connected together being located between the clamp jaws the clamp being selectively movable between an advanced position (20) in which it is located for use in connecting the timber pieces and a retracted position (20a) in which the clamp is removed from the general region (15) where the timber pieces are to be connected together so as to enable locating of timber pieces to be connected and removal of pieces after S connection; and a nail plate feed (25) for feeding nail plates (27) to the clamp jaws the nail plates (27) having projections which are embedded in Sthe timber pieces when the clamp jaws move towards each other, the nail plate feed (25) comprising a magazine (29) in which a number of pairs of facing nail plates (27) can be located and being arranged to feed to the clamp jaws (21), (22) two nail plates (27) with the projections of each nail plate being directed towards the other nail plate so that each one of the nail plates is associated with a respective clamp jaw (22) when the jaws are separated.