EP0015717B1

EP0015717B1 - Apparatus for connecting together a plurality of webs of flexible material

Info

Publication number: EP0015717B1
Application number: EP80300596A
Authority: EP
Inventors: Rodney Paul Williams
Original assignee: Williams Rodney Paul
Current assignee: Williams Rodney Paul
Priority date: 1979-02-28
Filing date: 1980-02-28
Publication date: 1989-07-26
Also published as: EP0015717A1; WO1980001778A1; CA1163848A; DE3072163D1; JPS56500248A

Description

The invention relates to apparatus for connecting together a plurality of webs of flexible material.
There are many areas where webs of flexible material need to be connected together, some of these being the securing together of a number of sheets of paper, for example in office use, the securing of packets to display cards, the securing together of parts of folded blanks to form cartons and other containers and the fastening together of two ends of a length of strapping for packaging applications.
There are many well-known methods of securing together webs of flexible material. Perhaps stapling machines are the most common example, but these have drawbacks in that the staples can be difficult to remove from the stapled sheets, the machines require constant reloading and staples are not completely interchangeable from one machine to another.
Attempts have therefore been made to fasten two or more webs of flexible material together without the use of auxiliary fastening elements such as staples. U.K. Patent Specification No. 508.663 (Hahn) describes and illustrates an apparatus in which a V-shaped tongue is punched out of a corner of one web and is then automatically threaded into a slit automatically cut into the other web. Another device working on this same principle is disclosed in U.S. Patent Specification No. 1,065,904 (Bumps). Devices of this type are relatively complicated in construction, they have many points of potential failure because they use a large number of working parts, and they are therefore relatively expensive and bulky: as a result, although they have been known for many years, they have so far failed to develop any permanent place on the market.
U.K. Patent Speicification No. 792,852 (Jewell) attempts to improve upon this slit-and-tongue type of fastener, and describes and illustrates an arrangement in which a basically circular tongue is punched through the folded corner region of the webs which are to be joined together. The apparatus described and illustrated in this Specification No. 792,852 is undoubtedly far less complicated than apparatus of the 508,663 kind; but it has the drawback that the connected webs are relatively easily separated from one another because the basically circular locking tab which is punched out of the webs allows the two webs to be all too easily rotated relative to one another so that the punched tab slides out of register with its co-operating circular slot.
Again, therefore, although the 792,852 device has been known for over twenty years, it has not-as far as I am aware-made any impact on the market. In general, despite its admitted drawbacks, the basic stapling machine continues to dominate the commercial market.
U.S. Patent Specification 3741 079 describes a method of splicing two webs of paper the ends of which overlap by punching identical tabs out of the two webs of paper leaving each tab attached to its web by a shank portion. However, this method allows relative longitudinal movement of the webs and the method may thus not be used to lock two webs together.
According to the present invention apparatus for connecting together a plurality of webs of flexible material comprises a base, an anvil incorporated in the base having an opening, at least part of which is defined by a first sharp edge, a punching head mounted for movement towards and away from the anvil, the punching head incorporating a punch at least part of which is delineated by a second sharp edge, characterised in that the apparatus further comprises means to fold the webs and to position the folded back parts and part of the remainder of the webs between the anvil opening and the punch and in that the first sharp edge of the opening on the anvil and the second sharp edge of the punch comprise a shank region and an elongated head region, the second sharp edge of the punch fitting closely within the first sharp edge of the punch fitting closely within the first sharp edge of the anvil and at least one of the punch and the anvil opening are devoid of a sharp edge adjacent the end of the respective shank region which is remote from the respective enlarged head region, so that when webs and the folded back part of the web are placed between the punching head and the anvil and the punch is moved into the anvil opening, the first and second sharp edges punch a portion of material having a shank and an enlarged head from each web and folded-over part of web, the portion of material remaining joined at the base of the shank to the associated web so that when the folded over piece of web is folded back to its original position the enlarged heads of the punched material are received in the narrow shanks of the openings left by other punched portions to lock the webs together.
To illustrate use of the apparatus if two sheets of paper are placed one on top of another, folded over at one corner to form four thicknesses and those four thicknesses are placed between the anvil opening and the punch and are then punched, it will be found that when the punched sheets are withdrawn from the apparatus they will be attached to one another. If the folded corner is smoothed back after punching the sheets will still remain attached to one another by virtue of the engagement of the enlarged heads of the punched portion engaging in the shank openings. The method is equally applicable to two sheets of flexible material other than paper, and also to more than two sheets of flexible material. If a substantial number of sheets are to be connected then it is found that it will suffice to fold over the corner of, say, the two uppermost and two lowermost sheets and to punch through the folded parts and the remainder of the sheets simultaneously. The same connecting effect as with two sheets is then obtained.
In all these cases the sheets can easily be separated from one another because only the punched portion holds them together. Furthermore, no materials other than the webs themselves are needed to maintain the connection, the use of separate fasteners such as staples being avoided. The apparatus avoids the complexity of devices of the kind shown in U.K. Patent Specification No. 508,663 whilst giving an altogether more positively-locked and less readily separated fastening than the apparatus of U.K Patent Specification No. 792,852.
Apparatus in accordance with the present invention may have uses other than simply connecting together superimposed pieces of paper or other material. For instance, the apparatus may be used for securing together the two ends of a length of strapping extending around a load. If the ends are brought together so that they are under tension around the load, pieces punched out using the apparatus of the invention and then the tension released, the ends of the strapping will move relatively apart and the enlarged head portion from one end will engage in the shank portion of the other end so that the strapping holds together in a secure condition. The use of apparatus in accordance with the invention in this way avoids the need for separate metal bands to surround the superimposed ends of the strapping and for crimping to be applied to these metal bands.
Apparatus in accordance with the present invention may also be used for securing packets to a display card, the packets containing, for instance, peanuts or other goods. The packets are laid over the display card and then the apparatus used to punch out pieces from both the packets and the display card. The packets remain attached to the display card because of the engagement of the enlarged head portion to the punched out pieces of one of the packet and the display card and with the shank portions of the other of the packet and the display card.
Apparatus in accordance with the present invention may also be used to join together two or more pieces of paper without the necessity for folding over the corners of the pieces of paper. For example apparatus in accordance with the present invention may be used to join together a plurality of sheets of paper, each sheet of paper being in the form of so-called continuous paper having transverse perforations extending across the width of the paper at spaced-apart intervals therealong. Such paper is for instance, widely used on printers used in many businesses, for instance, printers forming part of a computer. Such sheets of paper often having holes extending along one or both margins thereof at intervals of, say, about to 3" (6.35-12.7 mm). These holes are for engagement with peripherally spaced-apart lugs on one or more rollers of the printer.
It may be desired to form from two or more lengths of such paper, sets of two or more individual sheets. For instance, it may be desired to form sets of upwards of two sheets, being a stop sheet and copy sheets. In order to do this the continuous lengths have to be overlaid and the overlaid lengths then have to be separated transversely, either along their perforations or, if no perforations are provided, the overlaid sheets have to be cut at appropriate spaced-apart positions. However, the result would then be that the sheets of each set of sheets are not connected to the remaining members of the set. However, apparatus in accordance with the present invention allows the sheets to be connected together in a simple way, the connection together being, if desired, incorporated in a continuous process for bringing together the long lengths of paper and dividing them at a subsequent station or stations.
When the continuous lengths of paper are brought together correct superimposition is ensured by feeding them in such a way that the closely spaced-apart marginal holes engage with the pins or lugs on the feed rollers. Normally each sheet will be precisely superimposed so that, when perforations are provided, these exactly overlie each other. However, with the present invention, the apparatus is such that either the bottom or the top sheet is displaced relative to the other sheet or sheets. This displacement may be by one marginal hole. After the continuous sheets have come together in this way, apparatus in accordance with the present invention is used to punch out a hole at a position between each adjacent pair of perforations (in the case where the sheets have perforations or between each adjacent position where the sheets are to be cut where there are no perforations). This hole is punched through each superimposed sheet of paper at a position which may be, for instance, close to one or more of the afore-mentioned marginal holes. As before, the pieces of paper which are punched out remain attached to the corresponding sheets of paper at the bottom of the shank portions thereof.
Subsequently the superimposed continuous sheets of paper are fed to a further roller where these continuous sheets of paper are loaded onto the pins of the further roller in such a way that the previously displaced piece of paper is brought into exact alignment with the other sheet or sheets of paper. Thus the displaced sheet moves relatively to the other sheet or sheets and in so doing the same sort of engagement between the head portion of the punched out piece from one sheet takes place with the shank portion of the other or other sheets. As a result, the continuous sheets of paper are connected together at the positions along their lengths. Subsequent division of these continuous sheets of paper along transverse perforations or by cutting result in sets of sheets of paper, each set having the members thereof connected together.
The apparatus may further comprise guide means operative, as part of said webs advance into said apparatus, to fold said advancing parts back over the remainder of said webs and to position said folded-back parts and part of the remainder of said webs over said anvil opening.
In one form of the apparatus the mounting means comprises a pivotal connection between said base and said punching head located remote from said anvil opening and punch. In an alternative form the mounting means comprises guiding means for guiding said punching head along a reciprocal path towards and away from said base. In either case bias means may be provided for biasing the punching head away from the base so that the punching action takes place against the biasing force. The apparatus may be constructed in various forms ranging from lightweight hand-held devices designated for office use to power operated multi-anvil devices for industrial use.
In another form of apparatus in accordance with the present invention, the apparatus comprises a base, a punching head slidable relative to the base, a handle mounted on the base for pivotal movement relative thereto and a folding mechanism mounted on the base for pivotal movement thereto, the handle punching head and folding mechanism being operably connected together so that movement of the handle causes both the folding mechanism and the punching head to effect their pivotal movements.
The form of the defined part of the anvil opening and the delineated part of the punch is not critical as long as each has a respective shank region and enlarged head region. These combined regions could alternatively be described as a generally T-shaped slot and the punch shape includes all forms from a true T-shape through a key-hole shape to a triangular shape of which the narrow part can be considered a stem and the broader part an enlarged head.
The invention will be better understood from the following description of certain specific embodiments thereof, given, by way of example only, in connection with the accompanying drawings in which:-

Figure 1 is a perspective view of a first form of apparatus according to the invention;
Figure 2 is a side elevation of the apparatus shown in Figure 1;
Figure 3 shows, in views A to E plan views of five different anvils that may be used in the practice of the invention;
Figures 4 and 5 show respectively partial longitudinal cross-sections through alternative punch and anvil forms;
Figure 6 illustrates in partial schematic plan view use of apparatus which may be used to carry out a method of attaching packets to display card according to the invention;
Figure 7 is a cross-section on the line VII-VII of Figure 6;
Figure 8 is a vertical longitudinal section through another embodiment in accordance with the present invention;
Figure 9 is another longitudinal vertical section through the embodiment shown in Figure 8 but with the handle in its lowered position;
Figure 10 is a cross-section on the line TT of Figure 8;
Figure 11 shows the anvil member of the embodiment of Figure 8;
Figure 12 is a front elevation of part of the folder guide with the folder in its up position; and
Figure 13 is similar to Figure 12 but with the folder in its down position.

Referring now to Figures 1 and 2, these show a form of the apparatus designed for light office use. The apparatus consists of a metal base, which may be rubber-faced on its underside to give a non-slip standing surface. The top side of the base incorporates a hard steel anvil section 2 having a T-shaped slot 3 formed therein. The slot may be of limited depth or may extend completely through the base. The anvil section may be an integral part of the base or may be a separate insert into the material of the base and secured thereto by adhesive, screws or any other suitable means.
An elongate arm 4 is pivotally mounted at one end to the base about pivot pins such as 5. The arm has a punching head section 6 which may be integral with the arm or a separate part secured to the arm. The punching head section has incorporated therein a punch 7 which is again substantially T-shaped. A leaf spring 8 is secured to the base 1 by rivets 9 and is bent so that its free end engages the underside of the elongate arm 4 in order to bias that arm away from the base.
Two substantially U-shaped resilient wire guides 10 and 11 project upwardly from the base and are located one to each side of the anvil opening 3. Each guide has a lower part 12, 13 respectively which is located in a groove in the upper surface of the base 1 and held within the groove by, for example, a suitable adhesive. The bight 14, 15 respectively of each wire guide is located beyond the end 16 of the anvil opening 3. The free ends of the upper parts of the wire guides lies ahead of the opposite end 17 of the anvil opening. A further rectangular wire guide 18 projects forwardly from the base and in front of the guides 10 and 11, the ends of the guide 18 again being received in recesses within the base 1 and being secured thereto by a suitable adhesive or other means.
The form of the anvil opening 3 and the punch 7 is clearly seen from Figure 1. The whole of the opening is defined by a first sharp edge and comprises a shank region terminating at the end 16 and an enlarged head region terminating at the end 17, the whole being of substantially T-shape. The anvil opening and the punch are of substantially the same shape and the punch projects a given distance from the punching head and terminates in a web-contacting surface 19. A first part of the web-contacting surface is delineated by a second sharp edge and comprises the enlarged head region and that part of the shank region which is closest to the enlarged head region. A second part 20 of the web-contacting surface forms an extension from the shank region and tapers away from the first part of that surface towards the punching head. The tapered part of the surface blends smoothly into the remainder of the shank and the junction between the two is not sharp. The whole of the punch 7 is capable of fitting closely within the anvil opening 3.
To use the apparatus to connect together two sheets of paper the sheets 21, 22 are placed one on top of the other and corner of the combined sheets is then fed into the opening in the guide 18 from below the guide and into and around the guides 10 and 11 so that the corner will automatically be folded back on itself to the position shown in the drawings. Eventually the shape of the guide 18 will prevent the sheets of paper from being fed any further forward into the apparatus. The punching head can then be brought down onto the anvil against the action of the leaf spring 8. Four thicknesses of paper will be punched from the two folded over sheets and the punched T-shaped portions will be pushed through the sheets but will not be separated from them. Thus, the shank of each punched portion remains joined to the associated sheet due to the presence of the tapered section 20 of the punch and the fact that this does not include a sharp cutting edge transversely of the shank.
When the sheets are subsequently withdrawn from the apparatus, they will be found to be secured together at the folded corner. If the fold is opened out, the two sheets will stay secured to one another, with the enlarged head portions engaging behind the cut-out shank portions of the sheets.
Figure 3 shows a series of anvils having different shaped openings, each of which may be used with a correspondingly shaped punch in apparatus of the invention. The anvil A has a T-shaped opening which corresponds substantially to the opening shown in the apparatus of Figures 1 and 2. Anvil B has an opening which tends more towards a key-hole shape and also has a shank region and an enlarged head region. Anvil C has a triangular opening, which can be considered as having a stem comprising the narrower part 23 of the triangle and an enlarged head comprising the broader part 24 of the triangle. Anvil D has two openings 25 and 26 arranged side by side each of miniature key-hole form. Anvil E has a larger opening comprising a shank 27 and an enlarged square head 28. This latter anvil may be particularly useful in apparatus for securing together the two ends of a length of strapping extending around a load. If the ends are brought together and are punched on the anvil E with a punch head of the same shape, the shank of the punch tapering into the punch head as already described, then squares of the strapping material each secured to the material by a shank will be punched from the material. If tension in the strapping is then released the ends of the strapping will move relatively and the square heads will engage behind the slots so holding the strapping in a secure condition.
The apparatus shown in Figures 1 and 2 ensures that the punched portions of material remain attached to the main body of the material by tapering the punch head as at 20 so that the shank of material is not cut through. This result may be achieved alternatively by adopting either of the constructions shown in Figures 4 and 5. Each of these Figures shows a base 29 including an anvil opening 30 of substantially T-shape. A punching head 31 is positioned above the base and carries a substantially T-shaped punch 32. The whole of the punch is delineated by a sharp edge. In each case the anvil opening includes an extension 33 of the shank region beyond the end 34 of the shank region of the punch so that as the end enters the anvil opening there is no cutting effect on material laid between the punch and the anvil. The arrangement shown in Figures 4 and 5 differs only in that in the Figure 4 arrangement the extension 33 of the shank section tapers upwardly to meet the upper surface of the base, while in the Figure 5 embodiment no such taper is included.
Figures 6 and 7 shows schematically a form of apparatus that may be used for securing packets to a display card. The apparatus comprising a base 35 in which are incorporated a plurality of anvils each having an anvil opening 36 of generally key-hole form. Four guide pillars 37 extend upwardly from the base and guide thereon a punch carrier 38 supported above the base. Compression spring 39 may surround each of the pillars 37 to bias the carriers away from the base. The carrier 38 carries a punching head 40 which on its lower surface has a plurality of key-hole shaped punches 41, each arranged to engage within a respective one of the anvil openings 36. Each punch 41 has an enlarged head and a shank, both delineated by a sharp edge, and a shank extension 41 which tapers smoothly to meet the punching head, so that as the punch engages the anvil opening a key-hole-shaped piece of material is punched out but is left attached to the remainder of the material as already described. A display card 42 with its front side uppermost is fed into the apparatus and packets such as 43 are provided to be secured to the card. The drawing shows two packets to be attached to the card side by side in a series of rows but it will of course be appreciated that by proper choice of anvil and punches a greater number of packets can be attached. Each packet is laid on the card with its front side downwards and with its upper edge folded over as at 44 to give a double thickness, a strip of card 45 being folded around the folded edge of the packet as best seen from Figure 7. With the packets and card strip arranged as shown in this Figure the punch carrier is lowered towards the base either manually or under power and the punches punch through the two thicknesses of strip 45, two thicknesses of packet 44 and single thickness of display card 42. The card may then be advanced in the direction of the arrow shown in Figure 6 and a further two packets placed on the card in the positions outlined by the broken lines 46, whereupon the punching operation may be completed. When the required number of packets have been punched to the card in this way the card is taken from the apparatus can can be used for display with the edge 47 of the card uppermost, the packets falling and unfolding to lie adjacent the card with the strip 45 uppermost. The packets may then be pulled individually from the card as required.
It will be understood that, rather than attach packets to the card one row at a time as described with reference to Figures 6 and 7 a larger form of the apparatus may be constructed desiged to punch a plurality of packets in each of a plurality of rows to the card simultaneously.
Referring to Figures 8 to 13, another embodiment of apparatus in accordance with the present invention, particularly light apparatus for office type use, includes a base 51 within which a punch 55 is mounted for slidable longitudinal movement within guide 53. The front end 57 of punch 55 carries key-hole shaped punch members (not shown), each punch member having an enlarged head and shank, both delineated by a sharp edge and a shank extension which, as is the case with the previously described embodiment, tapers smoothly to meet at the punch head 57.
An anvil 59, in the form of a die plate, is located forwardly of the punch and fixed to the base or to an extension of guide 53 by rivets or the like through fixing holes 61. As will be described below, punch 55 can be slidably moved from a first position shown in Figure 8 to a second position, shown in Figure 9, in which the punch members on the head 57 of the punch 55 pass through anvil openings 63. Each anvil opening 63 has a shank and an enlarged head portion matching the shape of the above-mentioned punch members.
Attached by means of rivets (not shown) to base 51 are upwardly extending side plates 67. Extending through side plates 67 at a forward upper position thereof is a pin 69 on which is mounted for pivotal movement thereon a handle 71. As can best be seen in Figure 8, handle 71 extends rearwardly from pin 69 terminating at a position above the rear end of base 51. Handle 71 is shown in its rest position in Figure 8 but downward pressure applied to the rear end of handle 71 will cause it to move from the position shown in Figure 8 to the position shown in Figure 9.
Connecting levers 73 and 75 are each mounted at one end thereof for pivotal movement on a pin 77. Pin 77 is fixed at each end to handle 71. Connecting levers 73 and 75 terminate at their other end at a pin 79 on which they are pivotally mounted. Also pivotally mounted on pin 79 and located inwardly of connecting levers 73 and 75 are operating levers 80 and 81. These operating levers extend upwardly from pin 79 to a further pin 82 on which they are also pivotally mounted. Pin 82 is fixed at each end to side plates 67. Operating levers 80 and 81 extend downwardly from pin 79 to the rear end of punch 55 on which they are again pivotally mounted.
Pin 79 also passes through a slot 83 of folder control plate 87. As can be seen in Figure 10, folder control plate 87 is located centrally between the pair of operating levers 80 and 81 and, outwardly of the latter, the pair of connecting levers 73 and 75. The shape of folder control plate 87 can best be seen in Figures 8 and 9. It is roughly rectangular in shape with, at its front end, neck portion 89 and head portion 91. At its rear end it is mounted for pivotal movement on pin 93, the latter being fixed at each end to side plates 67.
Surrounding a substantial area of the front portion of each side plate 67 is a channel section bracket 95. The central bight section 97 of bracket 95 extends transversely across the front of the side plate 67 there being a small gap 99 between bight section 97 and the front edges of side plate 67. Mounted for sliding movement within this gap is folder 101. Folder 101 is substantially rectangular in shape but has a lower central cut out portion 103 and an upper substantially square shaped hole 105 through which extends the head portion 91 of folder control plate 87.
A tension spring 104 is fastened at one end to the rear of punch 55 and at its other end to the back of guide 53 within base 51.
In order to connect together two or more pieces of paper using the above-described device, the superimposed pieces of paper 105 are fed over the front of base 51 and below the bottom forward end of handle 71 and folder 101 to the position shown in Figure 8 where the corners of the superimposed pieces of paper 105 abut against the side plates 67. Handle 71 is then depressed. Handle 71 is linked to pin 79 by way of connecting levers 73 and 75 and as a result of the downward movement of handle 71 pin 79 is caused to move in a substantially horizontal forward direction. As a result of this movement and of the location of pin 79 within slot 83 of folder control plate 87. The latter is caused initially to pivot upwardly about pin 93. This is because of the downward travel of the first upwardly extending arm of inverted V-shaped slot 83 during the forward movement of pin 79. After pin 79 has reached the apex of the V-shaped slot 83, further forward movement of pin 79 causes the folder control plate to reverse the direction of its pivotal movement about pin 93 and move upwardly. Accordingly depression of handle 71 from the position shown in Figure 8 to the position shown in Figure 9 causes movement of folder 101 first downwardly and then upwardly as a result of the engagement of head portion 91 within square shaped slot 105 of folder 101.
In an alternative embodiment the forward downwardly extending portion of slot 83 may be replaced by a forward horizontally extending portion. In this case the movement of the folder, as a result of depression of the handle, is only in a downwards direction. This downward movement continues until the pin reaches the centre of the slot and then further downward movement of handle 71 does not result in any change of position of the folder. It has, however, been found that neater, more effective results are obtained when the folder returns to its up position after effecting folding of the sheets of paper.
During its downward movement, the bottom edges of folder 101 engage papers 105 to fold them at the corners thereof to the approximate confirmation shown in Figure 9, although Figure 9 shows the situation after the folder has returned to its up position and the papers have been _'engaged by punch 55.
The above-mentioned forward movement of the pin 79 also effects forward movement of operating levers 80 and 81 about pin 82. Because operating levers 80 and 81 are connected at their lower ends to punch 55 this effects in turn forward movement of punch 55. This forward movement continues during the whole of the downward movement of handle 71 and the head 57 of punch 55 engages the folded papers 105 just as the folder 101 is beginning its return upward movement. Subsequent forward movement of punch 55 results in punch members pressing the folder papers against anvil plate 59 and then passing through the layers of papers and through the anvil openings 63. The punched out pieces of paper remain attached to the sheets 105 at the bottom of the shank portions of the punched out pieces because of the rearward tapering of the shank extensions of the punch members. The punched out pieces are otherwise pushed through the anvil openings to a forward position thereof.
Release of the downward pressure on handle 71 allows the tension spring 104 to return to its original position thereby returning punch 55, operating levers 80 and 81, folder control plate 87 (carrying with it folder 101), connecting levers 73 and 75 and handle 71 back to their original positions. The sheets of paper 105 can then be removed. On unfolding them, they are found to be secured together because of the engagement of the enlarged head portions from the pieces cut out nearest to the corners of the sheets of paper 105 with the shank portions of the pieces cut out from positions further from said corners. In effect the sheets of paper 131 are "stitched" together by the punched out pieces when said sheets are unfolded.

Claims

1. Apparatus for connecting together a plurality of webs of flexible material, comprising a base (1), an anvil (2) incorporated in the base (1) having an opening (3), at least part of which is defined by a first sharp edge, a punching head (6) mounted for movement towards and away from the anvil (2), the punching head (6) incorporating a punch (7) at least part of which is delineated by a second sharp edge, characterised in that the apparatus further comprises means to fold the webs and to position the folded back parts and part of the remainder of the webs between the anvil opening (3) and the punch (7) and in that the first sharp edge of the opening (3) on the anvil (2) and the second sharp edge of the punch (7) comprise a shank region (16, 20) and an enlarged head region (19, 17), the second sharp edge of the punch (7) fitting closely within the first sharp edge of the anvil (2) and at least one of the punch (7) and the anvil opening (3) are devoid of a sharp edge adjacent the end of the respective shank region (16, 20) which is remote from the respective enlarged head region (19, 17), so that when the webs and the folded back part of the web are placed between the punching head (6) and the anvil (2) and the punch (7) is moved into the anvil opening (3), the first and second sharp edges punch a portion of material having a shank (16) and an enlarged head (17) from each web and folded-over part of web, the portion of material remaining joined at the base of the shank (16) to the associated web so that when the folded over piece of web is folded back to its original position the enlarged heads (17) of the punched material are received in the narrow shanks (16) of the openings left by other punched portions to lock the webs together.

2. Apparatus according to claim 1, in which the means to fold the webs comprises guide means (18) arranged so that, as part of the plurality of webs (21, 22) are advanced into the apparatus, the advancing parts are folded back over the remainder of the webs.

3. Apparatus according to claim 1 characterised in that the anvil opening (3) and the punch (7) are of substantially the same shape, the punch (7) projects a given distance from the punching head and terminates in a web contacting surface, a first part of the web contacting surface is delineated by the second sharp edge to comprise the shank region and the enlarged head region (19) and a second part of the web contacting surface forms an extension (20) from the shank region and tapers away from the first part towards the punching head the first and second part having a junction which is not sharp.

4. Apparatus according to claim 1, 2 or 3 characterised in that the anvil (2) has an upper surface, the opening (3) is formed through the surface and comprises a first part defined by the first sharp edge and a second part forming an extension of the shank region remote from the enlarged head region, the second part having a lower wall (33) which tapers upwardly to join the upper surface.

5. Apparatus according to any of the preceding claims characterised in that the punch (7) is wholly delineated by the second sharp edge and the anvil opening (3) comprises a first part defined by the first sharp edge and the second part forming an extension of the shank region remote from the enlarged head region.

6. Apparatus according to any of the preceding claims characterised in that a plurality of similar openings (3) are incorporated in the anvil (2) and a plurality of similar punches (7) are incorporated in the punching head (6), each one of the punches having a delineated part capable of fitting closely within a defined part of the respective opening.

7. Apparatus according to any of the preceding claims characterised in that the base (1) is pivotally connected to the punching head (6), the pivotal connection (5) being located remote from the anvil opening (3) and the punch (7).

8. Apparatus according to claim 1 characterised in that the apparatus including a base (51), a a punching head (55) slidable relative to the base (51), a handle (71) mounted on the base for pivotal movement relative thereto and a folding mechanism (101) mounted on the base (51) for pivotal movement thereto, the handle (71), the punching head (55) and folding mechanism (101) being operably connected together so that movement of the handle causes both the folding mechanism and the punching head to effect their pivotal movements.

9. Apparatus as claimed in claim 1 characterised in that said mounting means comprises guiding means for guiding said punching head along a reciprocal path towards and away from said base.

10. A method of connecting together a plurality of webs of flexible material comprising folding the plurality of webs, punching a hole through the plurality of folded webs so that the hole passes through the folded part of the web and the remaining part of the web, each hole defining a punched portion and a remaining opening including an enlarged head and narrow shank and having a base at which the punched portion remains connected to the associated web, and then unfolding the punched web so that the enlarged heads of some of the punched portions are received within the narrow shanks of the openings left by other punched portions to lock the webs together.