GB2251564A - A method and tool for forming a hinge leaf - Google Patents

Abstract

A tool (1) for forming a hinge leaf (2) of a hinge (3) comprises a pair of platens (25) and (26) movable towards each other into an operative position on a pair of upstanding columns (29). A blanking station (35) for forming a blank of the hinge leaf is mounted on the platens (25) and (25). A punching station (36) for punching holes (20) in the hinge leaf (2) is mounted on the platens (25) and (26). A roll forming station (37) and a leading edge forming station (38) are mounted on the platens (25) and (26) for forming a rolled portion (15) of the hinge leaf (2), and a bending station (39) is also mounted on the platen (25) and (26) for forming a bend (22) in the hinge leaf (2). Accordingly, the tool (1) only requires one single set up to carry out all the operations on a blank to form a hinge leaf (2). <IMAGE>

Description

A METHOD AND TOOL FOR FORMING A HINGE LEAF The present invention relates to a method and tool for forming a leaf of a hinge from sheet metal, and the invention also relates to a hinge leaf as well as a hinge.

In general, hinges of sheet metal comprise a pair of hinge leaves with co-operating side edges, which are normally rolled to form a bore which defines a hinge axis. The leaves are assembled with the bores aligned.

A hinge pin is placed in the bores so that the hinge leaves may be hinged relative to each other about the hinge pin.

The manufacture of such hinge leaves is relatively complex and time consuming. In general, a plurality of tools are required for forming such a hinge leaf, each tool normally comprising a suitable punch and die for performing a single operation. Generally, a tool is provided with a die and punch for forming the blank of the hinge. leaf. Another tool with a die and punch is provided for punching holes in the blank. Another tool with a punch and die is provided for rolling the side edge of the hinge and in many cases more than one tool is required for rolling the side edge of the hinge.

Furthermore, should it be desirable to form a longitudinal bend in the hinge extending parallel to the hinge axis a further tool or tools with appropriate punches and dies is required. This thus adds considerably to the cost of producing such a hinge leaf and furthermore it adds to the complexity of the production of the hinge leaf.

There is therefore a need for a method and tool for producing a hinge leaf which overcomes these problems.

There is also a need for a hinge leaf and a hinge manufactured using the method and tool.

The present invention is directed towards providing such a method and tool and a hinge leaf and hinge.

According to the invention, there is provided a tool for forming a leaf of a hinge from sheet metal, the tool comprising a pair of platens movable towards each other from a spaced apart rest position to an operative position, a blanking station for forming a blank of the hinge leaf, a roll forming station for rolling portion of the blank adjacent a first side edge thereof for forming a bore for receiving a hinge pin, the bore defining a hinge axis parallel to the first side edge of the blank, and a leading edge forming station for forming an elongated bend extending parallel to and adjacent to the first side edge of the blank to facilitate rolling of the first side edge, the blanking station comprising a blanking die means mounted on one platen, and a blanking punch means mounted on the other platen, the punch means and die means being movable together and co-operable with each other for forming at least one side edge of the blank on the platens being moved to the operative position, the leading edge forming station comprising a leading edge forming die means mounted on one of the platens and a leading edge forming punch means mounted on the other platen, and being movable towards each other and co-operable with each other on the platens being moved to the operative position for forming the bend adjacent the first side edge, and the roll forming station comprising a roll forming die means mounted on one of the platens and a receiving means mounted on the other platen, the receiving means being mounted relative to the roll forming die means for holding the blank and directing the blank with the leading edge directed into the roll forming die means for forming the rolled portion on the platens being moved to the operative position.

In one embodiment of the invention, the leading edge forming die means comprises a leading edge forming die having an elongated leading edge bend forming groove, and the leading edge forming punch means comprises an elongated punch rod extending parallel to the bend forming groove and having a partly curved surface cooperable with the groove for forming the leading edge bend. Preferably, the leading edge bend forming groove is of partly circular transverse cross section, and the punch rod is of substantially circular transverse cross section.

In one embodiment of the invention, the roll forming die means comprises a roll forming die having an elongated roll forming groove of partly circular transverse cross section, and the receiving means comprises a punch member having an elongated receiving slot extending therethrough for receiving the blank, the receiving slot extending substantially parallel to the roll forming groove.

Advantageously, the roll forming groove is of semicircular transverse cross section.

Additionally, the invention provides a method for forming a hinge leaf from sheet metal using the tool according to the invention, the method comprising the steps of entering the sheet metal into the blanking station and moving the platens to the operative position to form at least one side edge of the hinge leaf blank, placing the formed blank between the leading edge forming die means and the leading edge forming punch means of the leading edge forming station, and moving the platens to the operative position for forming an elongated bend extending parallel to and adjacent a first side edge of the blank to form a leading edge thereof, placing the blank in the receiving means of the roll forming station with the leading edge directed towards the roll forming die means and moving the platens to the operative position for rolling the side of the blank adjacent the first side edge to form a rolled position.

Preferably, the sheet metal is placed in the blanking station with a side edge of the sheet metal abutting the abutment member.

Further, the invention provides a hinge leaf formed according to the method of the invention, and the invention also provides a hinge leaf formed on the tool according to the invention.

Further, the invention provides a hinge comprising the hinge leaf according to the invention.

The invention will be more clearly understood from the following description of a preferred embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a tool according to the invention for forming a hinge leaf also according to the invention, Fig. 2 is a perspective view of portion of the tool of Fig. 1, Fig. 3 is an end elevational view of the portion of the tool of Fig. 3, Fig. 4 is a perspective view of another portion of the tool of Fig. 1, Fig. 5 is a perspective view of a further portion of the tool of Fig. 1, Fig. 6 is a front perspective view of another portion of the tool of Fig. 1, Fig. 7 is a rear perspective view of the portion of Fig. 6, Fig. 8 is an end elevational view of the portion of Fig. 6, Fig. 9 is an end elevational view similar to Fig.

8 illustrating the portion of the tool of Fig. 6 in a different position, Fig. 10 is a perspective view of another portion of the tool of Fig. 1, Fig. 11 is a perspective view of a hinge according to the invention, Fig. 12 is a sectional elevational view of the hinge of Fig. 11, Fig. 13 is a perspective view of a hinge leaf according to the invention from which the hinge of Fig. 11 is manufactured, Fig. 14 is a plan view of the leaf of Fig. 13 being formed, Fig. 15 is an end view of the leaf of Fig. 14, and Fig. 16 is a plan view of a blank from which the hinge leaf of Fig. 13 is manufactured.

Referring to the drawings, and initially to Figs. 1 to 10, there is illustrated a tool according to the invention indicated generally by the reference numeral 1 for forming a hinge leaf also according to the invention and indicated generally by the reference numeral 2 in Fig. 13. A hinge also according to the invention indicated generally by the reference numeral 3, see Figs. 11 and 12, is manufactured from two hinge leaves 2. The tool 1 is of the type which is suitable for mounting in a break press (not shown) as will be described below. Before describing the tool 1 in more detail, the hinge 3 and hinge leaf 2 will first be described with reference to Figs. 11 to 16.

The hinge 3 comprises a pair of identical hinge leaves 2 which are joined together, and pivotal about a hinge pin 6. Each hinge leaf 2 is formed of sheet metal from a blank 7 illustrated in Fig. 16 and described below.

The blank 7 comprises a first side edge 9 and a second opposite side edge 10 and end edges 11 and 12 joining the first and second side edges 9 and 10. Each hinge leaf 2 comprises a rolled portion 15 which forms a bore 16 for receiving the hinge pin 6. The bore 16 defines a hinge axis 17 of the hinge 3 about which the hinge leaves 2 pivot. Ends 19 of the hinge pin 6 are swaged to retain the hinge pin 6 in the bores 16. Two screw accommodating openings, namely holes 20, are provided in the hinge leaves 2. Side wings 21 in which the holes 20 are provided extend sidewardly from a longitudinal bend 22 in the hinge leaves 2 for engaging a side wall of a frame, and/or a closure member (neither of which are shown). The bend 22 extends parallel to the hinge axis 17.

The method for forming the hinge leaves 2 from sheet metal using the tool 1 is described in detail below.

However, briefly, the blank 7 is formed having the sides 9 and 10 and the end edges 11 and 12. The holes 20 are formed in the blank 7, and the rolled portion 15 is then formed. Prior to forming the rolled portion 15, a bend 23 is formed in the blank 7 slightly spaced apart from the first side edge 9 and parallel thereto to form a leading edge 24 to facilitate the formation of the rolled portion 15 as will be described below.

The bend 22 is finally formed in the blank 7.

Returning now to the tool 1, and referring to Fig. 1, the tool 1 comprises a lower platen 25 and an upper platen 26 which define a front face 27 and a rear face 28 of the tool 1. A pair of elongated upstanding columns 29 extend upwardly from the lower platen 25 and slidably engage respective linear bearings 30 mounted in and extending from the upper platen 26. The upper platen 26 is movable from a rest position illustrated in Fig. 1 towards the lower platen 25 to an operative position with rectilinear motion. This action of such tools will be well known to those skilled in the art.

A pair of buffers 32 extending from the lower platen 25 engage corresponding buffers (not shown) extending from the upper platen 26 to limit the travel of the upper platen 26 when the upper platen 26 is in the operative position. A mounting boss 31 is provided on the upper platen 26 for releasably engaging a piston rod (not shown) of a ram (also not shown) on the break press (not shown). In practice, the lower platen 25 is placed on a table of the break press and secured thereto by suitable clamping brackets (not shown).

Such mounting arrangements of tools in a break press will be well known to those skilled in the art.

A plurality of forming stations for forming each hinge leaf 2 are mounted in the tool 1. A blanking station 35 forms the blank 7 of the hinge leaf 2. A punching station 36 forms the holes 20 of the hinge leaf 2. A roll forming station 37 forms the rolled portion 15 of the hinge leaf 2, while a leading edge forming station 38 forms a leading edge on the blank prior to forming the rolled portion 15. In this embodiment of the invention, the leading edge forming station 38 and roll forming station 37 are incorporated as a single station in the tool 1. A bending station 39 forms the bend 22 of the hinge leaf 2. For convenience, the stations 35 to 39 will be separately described.

Referring in particular to Figs. 2 and 3, the blanking station 35 comprises a blanking die means and a blanking punch means. The blanking die means comprises a blanking die 40 which is secured by screws (not shown) to the lower platen 25. The blanking punch means comprises a blanking punch 41 which is secured to the upper platen 26 by screws (not shown). The blanking die 40 and blanking punch 41 are provided with respective co-operating cutting edges 42 and 43 for cutting a strip of sheet metal for forming the first and second side edges 9 and 10 of the blank 7 as the upper platen is moved into the operative position.An abutment member formed by an abutment bracket 45 is adjustably secured by screws (not shown) to the lower platen 25, and defines an abutment surface 46 for engaging a second side edge of a blank 7, while the first side edge 9 is being cut by the cutting edges 42 and 43, as will be described below. The abutment bracket is located on the lower platen 25 so that the distance from the abutment surface 24 to the cutting edge 43 of the die 40 is identical to the length between the first and second side edges 9 and 10 for accurately determining the length between the first and second cutting edges 9 and 10 and for ensuring that the side edges 9 and 10 and end edges 11 and 12 are respectively parallel and at right angles to each other.An opening 48 in the lower platen 25 accommodates the formed blanks 7 as they are formed for delivery into a bin (not shown) or other suitable collecting means mounted below the table (not shown) of the break press (also not shown).

This blanking station 35 is suitable for forming the blanks 7 from an elongated strip of metal the opposite side edges of which are parallel to each other and are spaced apart a distance corresponding to the distance between the end edges 11 and 12 of the blank 7 so that the side edges of the elongated strip of metal form the end edges 11 and 12 of the blank 7 without any further cutting or treatment of the end edges 11 or 12 being required. First guide means for guiding the strip of metal into the blanking station 35 comprises a guide member 50 mounted on the blanking die 40 and secured thereto by screws 51. The guide member 50 also acts as a second guide means for the punching station 36 as will be described below. A recess 52 formed in the guide member 50 co-operates with the blanking die 40 to form a guide passage 53 through which the elongated strip of metal is fed into the blanking station 35 for forming the blanks 7. Surfaces 55 of side walls 54 defining the recess 52 are parallel to each other and are aligned at right angles to the abutment surface 46 of the abutment bracket 45 which is also aligned at right angles to the cutting edges 42 and 43.

Furthermore, the spacing between surfaces 55 of the walls 54 is such as to provide a relatively tight sliding fit for the elongated strip of metal through the guide passage 53. In other words, the distance between the inner surfaces 55 of the side walls 54 is just greater than the distance between the end edges 11 and 12 of the blank 7.

Referring to Figs. 1 and 4, the punching station 36 comprises an opening forming die means and an opening forming punch means for forming the screw accommodating holes 20 in the blank 7. The opening forming die means comprises an opening forming die 58 and the opening forming punch means comprises an opening forming punch 59. The opening forming die 58 is secured by screws (not shown) to the lower platen 25 while the opening forming punch 59 is secured by screws (not shown) to the upper platen 26. In this embodiment of the invention, the opening forming die 58 is formed integrally with the blanking die 40 and comprises a pair of spaced apart bores 60 for forming the holes 20.

Only one of the bores 60 is visible in Fig. 4. A pair of punch members 61 extend downwardly from the opening forming punch 59 and co-operate with and extend into the bores 60 for punching the holes 20 in the blank 7 on the upper platen 26 being moved into the operative position. The second guide means are also formed by the guide member 50 for guiding and aligning the blank 7 in the punching station 36. The second guide means comprises a guide recess 63, see Fig. 5, formed in the guide member 50 which co-operates with the opening forming die 58 to form a receiving compartment 64 for receiving the blank 7 aligned in the punching station 36.Inner surfaces 65 of one of the side walls 54 and a side wall 66 forming the recess 63 are parallel to each other and spaced apart a distance corresponding to the distance between the end edges 11 and 12 of the blank 7 to facilitate a sliding fit of the blank 7 into the receiving compartment 64. An end wall 67 forms an abutment surface 68 for engaging the second side edge 10 of the blank 7 so that the blank 7 is correctly aligned with the punch members 61 and bores 60 for forming the holes 20. Openings 69 in the guide member 50 accommodate the punch members 61.

Referring now in particular to Figs. 6 to 9, the roll forming station 37 and leading edge forming station 38 will now be described. As mentioned above, the roll forming station 37 and leading edge forming station 38 are integrally formed as a single station and comprise a die 74 and a punch 75 mounted respectively on the lower platen 25 and the upper platen 26 by screws (not shown). Dealing initially with the leading edge forming station 38, the leading edge forming station 38 comprises a leading edge forming die means, namely, an elongated bend forming groove 76 formed in the die 74 for forming the bend 23 to form the leading edge 24. A leading edge forming punch 78 in the punch 75 carries an elongated punch rod 79 welded to the punch 78 and extending parallel to the bending grooves 76.The punch rod 79 is co-operable with the bending groove 76 for forming the bend 23 when the upper platen 26 is moved into the operative position. First alignment means comprising a pair of spaced apart stop members 80 extend upwardly from the die 74 for engaging the first side edge 9 of the blank for aligning the blank 7 on the die 74 for forming the bend 23.

A roll forming die means, namely, a roll forming groove 82 is formed in the die 74, and is parallel to the bending groove 76. The roll forming groove 82 is of semi-circular transverse cross section and engages the leading edge 24 of the blank 7 for forming the rolled portion 15, see Figs. 8 and 9. Receiving means for receiving the blank 7 with the leading edge 24 extending downwardly and directed into the roll forming groove 82 comprises a pair of receiving slots 84 in the punch 75. A recess 85 formed in a portion 86 of the punch 75 defines with a pair of downwardly directed members 87 the slots 84. The members 87 are secured by screws (not shown) to the portion 86 which is in turn secured by screws (also not shown) to the punch 78.An end wall 90 forming the recess 85 defines an abutment surface 91 for engaging the second side edge 10 of the blank 7, so that as the upper platen 26 is moved towards the operative position as illustrated in Fig.

9, the abutment surface 91 engages the second edge 10 of the blank 7, thereby forcing the leading edge 24 of the blank 7 into the roll forming groove 82 to form the rolled portion 15, as can clearly be seen in Fig. 9. A support member 92 extending upwardly from the die 74 supports the blank 7 to avoid the blank 7 buckling rearwardly during formation of the rolled portion 15.

The members 87 are spaced apart to provide clearance for the support member 92 therebetween.

Referring now in particular to Figs. 1 and 10, the bending station 39 comprises a bending die means, namely, a bending die 94 mounted on the lower platen 25 and secured thereto by screws (not shown), and a bending punch means, namely, a bending punch 95 mounted on the upper platen 26 and secured thereto also by screws (not shown). The bending die 94 comprises an elongated V-shaped groove 96 for forming the bend 22 in the hinge leaf 2. A portion 97 of the bending punch 95 is of V-shaped transverse cross section and co-operates with the groove 96 for forming the bend 22 when the upper platen 26 is moved into the operative position.

Second alignment means, namely, a stop member extends from the bending die 94 engage the second side edge 10 of the blank 7 for aligning the blank in the bending station 39 for forming the bend 22 at a predetermined distance from the second side edge 10.

In use, the tool 1 is mounted in a break press (not shown) with the lower platen 25 secured by suitable mounting brackets (not shown) on a table (not shown) of the break press. The upper platen 26 is mounted on the piston rod (not shown) of the ram (also not shown) of the break press. The piston rod is entered into and secured in the mounting boss 31 by suitable mounting means (also not shown). Such mounting means will be well known to those skilled in the art. With the upper platen 26 in the rest position raised above the lower platen 25 and the respective punches 41, 59, 75 and 95 raised above the corresponding dies 40, 58, 74 and 94, a strip of sheet metal from which the blanks 7 are to be formed is entered from the front face 27 of the tool 1 into the blanking station 35 through the guide passage 53. As discussed above, the width of the strip of sheet metal corresponds to the width between the end edges 11 and 12 of the hinge leaf 2. The sheet metal strip is entered through the guide passage 53 until the free end of the sheet metal strip engages the abutment surface 46 of the abutment bracket 45. The break press is then activated and the upper platen 26 is moved into the operative position 25 so that the cutting edges 42 and 43 of the blanking die and blanking punch 40 and 41, respectively, co-operate with each other for cutting the blank 7 from the sheet metal strip. Thus, the first side edge 9 of the blank 7 is formed by the cutting edges 42 and 43, and the free end of the sheet metal forms the second side edge 10.To form the next blank, the sheet metal strip is advanced until the just cut edge of the sheet metal strip engages against the abutment surface 46 of the abutment bracket 45 and the break press is again activated for forming the next blank 7. This operation continues until a desired number of blanks 7 have been formed. In each case, as the cutting edges 42 and 43 of the blanking station 35 co-operate to cut a blank from the sheet metal strip, the first side edge 9 of one blank is formed, and the second side edge 10 of the next following blank is also formed.

The screw accommodating holes 20 are next formed in the punching station 36. The blanks are sequentially entered into the receiving compartment 64 so that the second side edge 10 tightly abuts the abutment surface 68 of the end wall 67 of the guide member 50. The break press is activated and the upper platen 26 is lowered into the operative position for punching the holes 20. The blank 7 with the holes 20 formed therein is removed from the receiving compartment 64 and the next blank 7 is entered into the receiving compartment 64.

The leading edges 24 are next formed in the blanks 7 by sequentially placing the blanks on the die 74 with the first side edge 9 of the blank 7 abutting the stop members 80 so that the leading edge bend 23 is formed parallel to the first side edge 9. The break press is activated and the upper platen 26 is moved into the operative position relative to the lower platen 25, thereby forming the leading edge bend 23. The blank is then inserted in the receiving slots 84 with the second side edge 10 of the blank adjacent the abutment surface 91 in the slots 84. The leading edge 24 of the blank 7 is directed downwardly into the roll forming groove 82 as illustrated in Fig. 8. The break press is activated and the upper platen 26 is moved into the operative position relative to the lower platen 25.As the upper platen 26 moves towards the lower platen 25, the abutment surface 91 engages the second side edge 10 of the blank 7. Further downward movement of the upper platen 26 urges the leading edge 24 into the roll forming groove 82, thus forming the rolled portion 15 as illustrated in Fig. 9.

The bend 22 is then formed in the blank 7 by placing the blank with the rolled portion 15 formed therein in the bending station 39. The second side edge 10 of the blank 7 is abutted against the stop members 98 so that the blank is correctly aligned in the bending station 39. The break press is then activated and the upper platen 26 moved into the operative position relative to the lower platen 25, thereby forming the bend 22 between the bending die 94 and the bending punch 95.

To form a hinge 3, a pair of hinge leaves 2 are connected together by the hinge pin 6 which is then secured in the bores 16 of the rolled portions 15 by swaging the ends 19 of the hinge pin 6, see Fig. 12.

While the tool 1 has been described in use with only one operation being carried out on the blank each time the upper platen 26 is moved into the operative position, if desired, blanks in various stages of formation may be placed in the appropriate stations 35 to 39, so that each time the upper platen 26 is lowered into the operative position, each station would perform an operation on a blank.

The advantages of the invention are many. A particularly important advantage of the invention is achieved by virtue of the fact that all the forming stations are mounted on the same tool. Accordingly, setting up time required to set up the tool is kept to a minimum. Additionally, all the operations required for forming a hinge leaf from a blank are carried out on a single break press, thus reducing the number of break presses required to form the hinge leaves.

Furthermore, by virtue of the fact that all the stations are mounted on the one tool, a single set up is all that is necessary to carry out all the operations to form a hinge leaf.

While the tool has been described as comprising a bending station for forming the bend 22 in the blank, the bending station if desired may be dispensed with.

Indeed, it is envisaged in many cases that hinges may be provided without the bends 22 in the hinge leaves.

Additionally, in certain cases, it is envisaged that the punching station may be dispensed with. It is also envisaged in many cases that hinges may be provided without screw accommodating holes in the leaves, and indeed, in many cases, it is envisaged that hinges may be provided without screw accommodating holes in the leaves.

Further, it is envisaged that leading edge forming grooves of other shape and construction may be provided. Indeed many other shapes and construction of punch rods may be provided. It is also envisaged that a roll forming groove of other shapes and construction may be provided, and it is also envisaged that a receiving slot of other shapes and constructions may be provided.

While the blanking station has been described for forming a straight first side edge, a first side edge of other shapes may be provided, and indeed, in certain cases, it is envisaged that the blanking station may form a first side edge which is stepped or which comprises a recess.

Further, it will be appreciated that it is not essential that the roll forming station and leading edge forming station be formed as an integral station.

Needless to say, where a punching station and bending station is provided, other suitable punching and bending stations may be used.

Claims (34)

1. A tool for forming a leaf of a hinge from sheet metal, the tool comprising a pair of platens movable towards each other from a spaced apart rest position to an operative position, a blanking station for forming a blank of the hinge leaf, a roll forming station for rolling portion of the blank adjacent a first side edge thereof for forming a bore for receiving a hinge pin, the bore defining a hinge axis parallel to the first side edge of the blank, and a leading edge forming station for forming an elongated bend extending parallel to and adjacent to the first side edge of the blank to facilitate rolling of the first side edge, the blanking station comprising a blanking die means mounted on one platen, and a blanking punch means mounted on the other platen, the punch means and die means being movable together and co-operable with each other for forming at least one side edge of the blank on the platens being moved to the operative position, the leading edge forming station comprising a leading edge forming die means mounted on one of the platens and a leading edge forming punch means mounted on the other platen, and being movable towards each other and co-operable with each other on the platens being moved to the operative position for forming the bend adjacent the first side edge, and the roll forming station comprising a roll forming die means mounted on one of the platens and a receiving means mounted on the other platen, the receiving means being mounted relative to the roll forming die means for holding the blank and directing the blank with the leading edge directed into the roll forming die means for forming the rolled portion on the platens being moved to the operative position.

2. A tool as claimed in Claim 1 in which the leading edge forming die means comprises a leading edge forming die having an elongated leading edge bend forming groove, and the leading edge forming punch means comprises an elongated punch rod extending parallel to the bend forming groove and having a partly curved surface co-operable with the groove for forming the leading edge bend.

3. A tool as claimed in Claim 2 in which the leading edge bend forming groove is of partly circular transverse cross section, and the punch rod is of substantially circular transverse cross section.

4. A tool as claimed in any preceding claim in which the roll forming die means comprises a roll forming die having an elongated roll forming groove of partly circular transverse cross section, and the receiving means comprises a punch member having an elongated receiving slot extending therethrough for receiving the blank, the receiving slot extending substantially parallel to the roll forming groove.

5. A tool as claimed in Claim 4 in which the roll forming groove is of semi-circular transverse cross section.

6. A tool as claimed in Claim 4 or 5 in which the leading edge bend forming groove of the leading edge forming station and the roll forming groove of the roll forming station are substantially parallel to each other and arranged side by side relative to each other.

7. A tool as claimed in any preceding claim in which the tool comprises a punching station for punching an opening in the blank of the hinge leaf.

8. A tool as claimed in Claim 7 in which the punching station comprises an opening forming die means mounted on one of the platens and an opening forming punch means mounted on the other platen, the die means and punch means being movable towards each other and being co-operable with each other for punching the opening on the platens being moved to the operative position.

9. A tool as claimed in any preceding claim in which the tool comprises a bending station for forming a substantially longitudinal bend in the blank of the hinge leaf substantially parallel to the hinge axis, the bending station comprising a bending die means mounted on one of the platens and a bending punch means mounted on the other platen, the die means and punch means being movable relative to each other and cooperable with each other for forming the bend on the platens being moved to the operative position.

10. A tool as claimed in Claim 9 in which the bending die means comprises a bending die having an elongated V-shaped groove for forming the bend, and the bending punch means comprises a bending punch of V-shaped transverse cross section substantially corresponding to the transverse cross section of the V-shaped groove.

11. A tool as claimed in any preceding claim in which the blanking die means and the blanking punch means form the first side edge of the blank of the hinge leaf.

12. A tool as claimed in Claim 11 in which the blanking punch means and the blanking die means define respective co-operable elongated cutting edges for forming the first side edge.

13. A tool as claimed in Claim 12 in which an abutment member is provided adjacent the blanking station spaced apart from the said cutting edges of the blanking die and punch for engaging a side edge of the blank for aligning a piece of sheet metal with the said cutting edges for forming the first side edge.

14. A tool as claimed in any preceding claim in which a first guide means is provided for guiding a piece of sheet metal into the blanking station for forming the first side edge.

15. A tool as claimed in any of Claims 7 to 14 when dependent on Claim 7 in which a second guide means for guiding the blank into the punching station for punching an opening is provided.

16. A tool as claimed in any preceding claim in which first alignment means are provided in the leading edge forming station for aligning the blank with the leading edge forming punch and die means.

17. A tool as claimed in any of Claims 9 to 16 when dependent on Claim 9 in which second alignment means are provided in the bending station for aligning the blank with the bending punch and die means.

18. A tool as claimed in any preceding claim in which one of the platens is a lower platen and the other of the platens is an upper platen mounted above the lower platen, the said punch means and receiving means being mounted on the upper platen and the said die means being mounted on the lower platen.

19. A tool as claimed in Claim 18 in which a pair of parallel guide columns extend upwardly from the lower platen and slidably engage the upper platen.

20. A tool as claimed in Claim 18 or 19 in which the said punch means and receiving means are mounted side by side on the upper platen, and the said die means are mounted side by side on the lower platen, and are enterable from a front face of the tool.

21. A tool for forming a leaf of a hinge, the tool being substantially as described herein with reference to and as illustrated in the accompanying drawings.

22. A method for forming a hinge leaf from sheet metal using the tool of any of Claims 1 to 21, the method comprising the steps of entering the sheet metal into the blanking station and moving the platens to the operative position to form at least one side edge of the hinge leaf blank, placing the formed blank between the leading edge forming die means and the leading edge forming punch means of the leading edge forming station, and moving the platens to the operative position for forming an elongated bend extending parallel to and adjacent a first side edge of the blank to form a leading edge thereof, placing the blank in the receiving means of the roll forming station with the leading edge directed towards the roll forming die means and moving the platens to the operative position for rolling the side of the blank adjacent the first side edge to form a rolled position.

23. A method as claimed in Claim 22 in which the sheet metal is placed in the blanking station with a side edge of the sheet metal abutting the abutment member.

24. A method as claimed in Claim 22 or 23 in which the method includes the step of placing the blank on the leading edge forming die means and engaging the first side edge of the blank with the first alignment means for aligning the blank with the leading edge forming die and punch means.

25. A method as claimed in any of Claims 22 to 24 in which the method further comprises the step of placing the blank between the opening forming punch means and the opening forming die means and moving the platens to the operative position for forming the opening in the blank.

26. A method as claimed in Claim 25 in which the blank is placed between the opening forming punch means and the opening forming die means immediately after the blank has been formed in the blanking station.

27. A method as claimed in any of Claims 22 to 26 in which the blank is placed in the bending station between the bending die means and the bending punch means and the platens are moved to the operative position for forming an elongated bend in the blank parallel to the first side edge thereof.

28. A method as claimed in Claim 27 in which the blank is placed in the bending station after the rolled position is formed in the roll forming station.

29. A method for forming a hinge leaf from sheet metal, the method being substantially as described herein with reference to and as illustrated in the accompanying drawings.

30. A hinge leaf formed according to the method of any of Claims 22 to 29.

31. A hinge leaf formed on the tool of any of Claims 1 to 21.

32. A hinge leaf substantially as described herein with reference to and as illustrated in the accompanying drawings.

33. A hinge comprising the hinge leaf of any of Claims 30 to 32.

34. A hinge substantially as described herein with reference to and as illustrated in the accompanying drawings.