This invention relates to equipment for the press tool production of metal elements.

Our Australian patent 484,003 deals with building frameworks comprised of interconnected frames each made up from a plurality of metal elements provided with tongues and slots allowing the elements to be assembled together into a frame. It is primarily for the manufacture of such elements that this invention has been devised.

Frame elements made of metal have many desirable qualities. For example, they are warp free which distinguishes them from timber frames which frequently warp as the timber elements from which they are made dry out. They are lighter than many timber members of similar strength as well as being vermin free. They have a long life and they lend

* themselves to factory manufacture and assembly.

To capitalise on the economies that flow from factory manufacture of the elements is it necessary to provide equipment that will make the required elements quickly and accurately. The ability to maintain the length dimension of elements within close tolerances is essential. The present invention provides a press tool set which will form the ends

of elements at a predetermine distance from locating means placed in the strip material from which the elements are to be cut in a preceding operation and as the strip moves continuously through the press tool set.

Broadly, the invention can be said to comprise a tool set to perform press tool operations on a continuously moving strip of metal in positions accurately located relative to predetermined register positions on the strip, said tool set including a first support member and a second support- member at least one of which is adapted to be moved towards and away from the other in a first direction, co-operating first and second press tool parts, guideways on both of said support members in which the first and second press tool parts are respectively mounted so as to be movable in unison away from and towards a rest position in a second direction at right angles to said first direction, bias means biassing said press tool parts towards said rest position, a locator on one of said press tool parts movable relative thereto between an extended position and a retracted position respectively in the path of and clear of the path of a strip of metal when it is advanced continuously in said second direction between said press tool parts, said locator being engagable when extended in a preformed register aperture in said strip to cause said press tool parts to move with said strip in said second direction away from said rest position, locator"moving means to extend and retract said locator.

support moving means to move said movable support(s) towards and away from each other to operatively engage and disengage said press tool parts, -and first control means to actuate said support moving means to operatively engage said press tool parts during the movement of said press tool parts in said second direction to perform a metal working operation on said strip.

A presently preferred embodiment of the tool set of the present invention will now be described with reference to the accompanying drawings in which:-

Fig.l is a diagrammatic view of a machine incorporating the tool set of the invention and associated equipment,

Fig.2 is a fragmentary sectional view of part of the tool set illustrated in Fig.l,

Fig.3 is a sectional elevation a second tool set shown in

Fig.l which forms part of the associated equipment, and

Fig.4 is a plan view of an end portion of a workpiece as manufactured by the tool sets illustrated in Fig.l and a scrap element between the ends of two such workpieces.

The machine is adapted to process channel members by cutting them to length and forming them at their ends and at selected positions along their lengths so that they will be interconnectable with other members thereby allowing frames to be assembled. As illustrated in Fig.l there is a machine including a bed 1, on which there is mounted two

tool sets A and B. The tool sets A and B respectively comprise a first lower support member 2 and a second lower support member 3 fixed, in spaced relationship to the bed. Above the lower support members there are upper support members 4 and 5 respectively slidably mounted on columns 6 fixed to the lower supports 2 and 3. The upper supports 4 and 5 are moved up and down by suitable means preferably mechanical devices including a clutch connected to a crank shaft as used in conventional power presses to perform stamping operations. The power means are indicated by the arrows 7 and 8.

The upper and lower support member pairs 2-4 and 3-5 are provided with guideways 9 in which upper and lower members 10-11 of a first die set and upper and lower members 12-13 of a second die set are mounted so as to be captive but movable on a common axis in a direction at right angles to the direction of movement indicated by arrows 7 and 8. The upper and lower members of each die set are interconnected by pillars and bushes 14-15 in known manner to maintain a working alignment between each upper die set member and its associated lower die set member whilst permitting the upper and lower die set members to move together and apart.

The die set member 11 is connected to the piston rod 16 of an air cylinder 17 mounted to the bed 1. During the working cycle of the machine air in the cylinder 17 urges the

piston rod 16 and the die set parts 10 and 11 to the left to bias them against stop means 18 which limits their travel in the direction away from the cylinder 17. A like cylinder 19 mounted on the bed 1 has a piston rod 20 fixed to the die set member 13. During the working cycle of the machine die set parts 12-13 are biassed towards engagement with stop means 21 which limits their travel away from the cylinder 19.

The upper die set member 10 has punches mounted therein and extending downwardly towards the bottom die set member 11 in which there are holes dimensioned to accurately receive the punches. As a strip workpiece passes between the die set, members 10-11 pieces the same size and shape as the cross-sections of the punches can be punched from the workpiece by moving the upper support 4, on which the die set member 10 is mounted, towards the lower support 2, on which the lower die set member 11 is mounted, so the punches to enter the holes.

The punches in the upper die set member 10 are of two shapes. The punch identified 22 has a cross-section which will form a hole as shown in Fig.3 in the back of a channel member with upturned flanges, as shown in Fig,.3. The hole has a part-circular part 23 with rectangular notches 24 at opposite sides of the hole on an axis that is co-incident with the long axis of the back of the channel. The punches

identified 25, there are two aligned so that only one is seen in edge view in Fig.l, produce a pair of slots as indicated 26 in the back of the channel.

The punch 22 can be isolated so that it will not perform a punching operation when the die set members 10 and 11 move together. This is achieved by means of the mechanism shown in Fig.2 comprising a slide 27 which is housed on the member 10 with a coupled piston rod 28 connected to a piston 29 slidable in a cylinder 30. By introducing air into the cylinder 30 at X the slide 27 is located in a cavity 31 where it lies between the upper head end 32 of the punch 22 and the face 33 of the cavity 31. It follows that if the slide 27 is above the punch head 32 when the upper die set member 10 descends the punch 22 is supported and the punch penetrates the workpiece and produces a hole the same shape as the punch and a waste piece the same shape as the punch. The waste piece passes through the hole in the die set member 11 and a hole in the support 2 and drops out below the machine. If the slide 27 is withdrawn when the die set member 10 descends the lower work end of the punch 22 will rest on the workpiece and as there is no support for the head 32 it will rise up into the cavity 31, the punch 22 is thereby retracted and there will be no hole formed in the workpiece.

The punching action of the punches 25 is likewise controlled

by a slide 34 on a piston rod 35 fixed to a piston 36 in a cylinder 37. The punches 25 can be separate elements each with a head 38 which withdraw into the cavity 39 if the slide 34 is withdrawn or the punches 25 can be joined and be of generally "U" shape. It is to be noted that the punches 25 always descend in unison.

The upper die set member 12 and the lower die set member 13 have co-operating punches and tools indicated generally as 40 to trim the end of a channel workpiece passing between the die set members 12 and 13 to provide tongues and an end configuration for the workpiece that will enable it to be combined with previously formed elements. The shape and configuration of the element ends are as shown in Fig.3 and comprise two tongues 41 aligned with the slots 26 and it will be seen that the end portion of the channel is swaged in to a width such that the width is equal to the width W between the flanges 42 of an unswaged portion of the channel. As will be understood this allows the swaged end to be entered into a like channel member used as a head plate or a foot plate in a wall frame. In this regard reference should be had to our patent 484,003 and the drawings thereof.

Located in the bottom die set member 13 there is a small air cylinder 49, see Fig.4. The piston 50 in the cylinder 49 has an extended end 48 which projects above the member 13

into the path of the workpiece passing through the die set when air is introduced below the piston 50 and when air is introduced above the piston 50 the end 48 is moved to a position below the path of the workpiece.

Having decribed in general detail the characterising features of the press tool the associated apparatus will be described. There is an associated roll forming and feeding roller set indicated generally 43. It comprises rollers of known type that form a flat strip of metal in passing through the rollers into a channel with the flanges upwardly directed and the back of the channel at an elevation substantially co-incident with the upper surface of the lower die set members 11 and 13. There are guides, not shown, on the members 11 and 13 to centralise the channel below the punches 22-55 and the tools 40 of the die set members 12-13.

There is a scanning device 44, which can be anyone of many types, that monitors the passage of the formed channel and records the passing in small increments, say every 2mms. In the preferred arrangement this takes the form of a wheel 45 which rolls on the surface of the advancing channel and a reader counts the passage of marks 46 arranged around the periphery of a circle past a mark detecting device, not shown. The reader is coupled to a control means which monitors the movement in the feed direction towards the work

stations and when a predetermined number of nuns, have passed a given datum point control signals are sent to the presses to cause the die sets to move in a closing manner in the direction of the arrows and to punch and/or swage the advancing channel member.

In a working sequence wherein channels are to be formed having a length which is for convenience a multiple of a predetermined unit length, say 75mms, the procedure would be as follows:-

The leading end of a coil of metal of a predetermined width would be fed into the forming rollers 43 and immediately the leading end passes below the wheel 45 it commences to rotate and counting of the marks 46 would commence, a predetermined number of marks would conveniently equal the unit length of 75mms. Generally, the control means for the apparatus will actuate the press 7 when a predetermined number of units have passed the datum point thereby indicating a given amount of channel has passed into the die set 10-11. Specifically, the arrangement is such that the clutch of the press 7 is actuated when the end of the channel, indicated 47 in Fig.3 has moved a predetermined amount beyond the centre of the punch 22. Depending upon whether the slides 27 and/or 34 are in or out the press will form a hole 23/24 or slots 26 or both. However, adjacent the leading end of each element being made the hole 23/24 must be formed as it

has a function in the formation of the channel end. When the punches penetrate the channel back they lock the channel to the die set members-10-11 and the die set members 10-11 are caused to advance in their slideways 9 as the channel continues to advance. When the press goes though its cycle and the punches are withdrawn from the channel the die set members 10-11 are returned to the rest position against stops 18 by the piston in the cylinder 17 which is always pressurised with compressed air, and the channel continues to advance without stop or decrease in speed.

In a typical arrangement the slots 26 would not be required but the slots 26A would be required. In such a case for the first press stoke the slide 27 would be in the IN position and the slide 34 would be in the OUT position, accordingly the punch 22 would cut and the punches 25 would not. After the first punching stroke the program of the control means which would have been previously compiled so as to provide the holes 26A would move the slide 27 to the OUT position and the slide 22 to the IN position and when the appropriate length of channel had passed the datum point the clutch of press 7 would be actuated by the control means. The die set members will come together and the punch 22 will rise up and not operate and the punch 25 will form the slots 26a. In this way, as determined by the control means, slots 26, 26A and holes 23/24 can be formed anywhere along the length of a channel.

It is to be noted that the press clutch incorporates a brake so that the press always stops with the upper member 4 in substantially the same position.

The holes 23/24 are service holes for the threading of services such as, wiring and plumbing through the frames. The first hole 23/24 formed in a member is also used for subsequent operations to be done on the channel. The slots 26 and 26A are for heads and noggins to be mounted in the manner described in detail in our patent 484,003.

When the leading hole 23/24 of the channel is located substantially centrally over the extension 48, a location determined from the counts made from the wheel 45, air is introduced into the cylinder 49 to raise the piston 50 and so the extension 48. The extension 48 is engaged by the face 51 of the notch 24 as the channel continues to advance resulting in the channel moving the upper and lower die set members 12-13 in their slideways 9. Movement of the members 12-13 causes a switch to be actuated to initiate the operation of the press 8. The tools 40 mounted in press 8 are for cropping and swaging the leading end of the channel as shown in Fig.3. When the crop and swage operation is complete and the tools 40 are moved apart to release the channel air is introduced into the cylinder 49 to cause the piston 50 and thus the extension 48 to retract. The

members 12-13 will be returned to the rest position against the stops 21 by the piston in the cylinder 19 which is always pressurised.

After the required number of length units have been counted off by the wheel 45 the press 7 is actuated again so as to at least provide a hole 23/24 which will be at the leading end of the following channel. As the channel advances and when the second hole 23/24 is located over the extension 48 air is introduced into the cylinder 49 to cause the extension 48 to be elevated and a die set movement will occur (as before) resulting in the actuation of the operation initiating switch for the press 8. A crop and swage sequence will occur, as before. In this operation the trailing end of the first channel length and leading end of the second channel length will be swaged at the same time and the lugs 41 will be formed on those ends and a scrap element, as indicated S in Fig.3, will be formed.

It follows that this process can go on without interruption until the coil of work strip being fed to the roll former is exhausted. Accordingly, studs, heads and noggins of the chosen length can be formed continuously without the forward movement of the strip through the roll formers 43 being stopped or slowed down.

As will be understood the machine functions as described are

ideally suited for control by computer program and the various operations would be performed in accordance with the characteristics of a required work-piece which could be written into a basic program from a keyboard. Press clutch actuation and air feeds to cylinders 30,37 and 49 can be initiated by the computer in accordance with signals received by it from the reading device 44.