Cleat for attaching handles to metal containers

Abstract: A cleat adapted to be secured to a metal container by projection welding has an annular flanged head portion (12) and a tubular shank portion (14) comprising legs (15) each having a sharp point (16) which will penetrate through paint or lacquer on the container, such as a paint can. The points (16) are preferably the result of the intersection of two shear cuts at right-angles in a flat strip which is then formed and cut to make the cleat.

Description: This invention relates to studs or rivets which are used for retaining respective opposite ends of a carrying handle on a container, such as a paint can. Normally, two such studs or rivets are fixed at diametrically opposite positions adjacent to the top of a cylindrical paint can. The invention also relates to a method of making such studs or rivets. It is known to apply such studs or rivets to a can by rivetting through the can. However, this is relatively costly. GB 1044442 describes a method of securing a trunnion piece to a container body. A dished metal trunnion piece has its base perforated by a cylindrical punch to create an annular jagged flange which will penetrate a coating on the body so as to make contact for electrical spot-welding. It is an object of the invention to provide a stud or rivet and a method of making the same which is inexpensive and not wasteful of material. The stud or rivet of the present invention is to be fixed to the can or other container by projection welding. In accordance with the present invention there is provided a stud or rivet adapted to be secured to a metal container by projection welding, the stud or rivet having an annular flanged head portion and a shank portion defining a plurality of sharp points, characterised in that the points are formed by the intersection of two shear cuts at right-angles. Because the stud or rivet will normally be welded to a can which has already been painted or lacquered externally, it is necessary for the projection welding process that the stud or rivet has a plurality of sharp projecting points which can penetrate the external paint layer and weld satisfactorily with the metal of the can, such as tin-plate. The present invention is also concerned with a method of manufacture of studs or rivets for containers, the method comprising the steps of making at least two intersecting shear cuts at right-angles to each other through a piece of strip material, forming the sheared area into a tubular portion having a plurality of sharp points, and removing the stud or rivet from the strip by cutting around the tubular portion thereby to form an annular flanged head portion from which the tubular portion extends. One presently preferred embodiment of stud or rivet and method of manufacture of studs or rivets in accordance with the invention will now be described by way of example, and with reference to the accompanying drawing, in which: Fig. 1 is a top plan view of the stud or rivet; Fig. 2 is a side view of the stud or rivet; Fig. 3 illustrates how the stud or rivet is manufactured by a shearing and forming process from strip material; and Fig. 4 shows how the studs or rivets can be made from strip material with minimum wastage. The stud or rivet, which is indicated generally at 10, can be made for example from mild steel having a plate thickness of for example 0.5 mm (0.02"). Alternatively stainless steel can be used. The stud or rivet has a head portion 12 in the form of an annular flange, and a tubular shank portion 14. As shown most clearly in Fig. 2, the tubular shank portion 14 has a configuration such that it defines four equispaced legs 15 with sharp points 16 at the apices of the four generally triangular legs of the shank. Preferably, four such sharp points 16 are provided. In the projection welding process by means of which the stud or rivet is secured to the can (which is a conventional process and will therefore not be described) these sharp points 16 will penetrate through the paint or lacquer on the can to the metal of the can to ensure a satisfactory weld. It is therefore essential that the points 16 are absolutely sharp. Fig. 3 illustrates how the stud or rivet can be manufactured, in a multi-stage process from metal strip material 18. The stages are carried out in a progression, the strip 18 being advanced in steps past the various working tools. As indicated at the right-hand end of Fig. 3 in the first two stages the strip 18 is sheared through its thickness, in two steps by two shear blades, each along a straight line 20a, 20b respectively, the lines being at right-angles to each other and thus defining a cross. At the next station the cross is located over a hole and a suitable punch is forced downwards on the circular area defined by the ends of the shear lines, making the splits open and thereby creating the generally triangular pointed legs 15 of the shank. Because the points 16 at the apices of the legs are formed by the intersection of two shear cuts at right-angles they are absolutely sharp. At the next station a pilot device is provided to ensure that the pitch is correct and that the holes are accurately in register. At the final station a blanking tool is used to cut the outside circumference, following which the stud or rivet falls through a hole in the press tool into a collecting device. Although the manufacture of studs or rivets in a single line as shown in Fig. 3 gives good utilisation of material and hence is inexpensive, further savings can be made by the use of multiple tooling and by making the studs or rivets in a plurality of rows across the width of the strip, as shown in Fig. 4. By staggering the rows as shown one keeps waste material to a minimum. After the stud or rivet has been welded at its points 16 to the can or other container, the carrying handle is fitted over the stud or rivet, to seat behind the annular flanged head 12.

Claims: A stud or rivet adapted to be secured to a metal container by projection welding, the stud or rivet having an annular flanged head portion (12) and a shank portion defining a plurality of sharp points (16), characterised in that the points (16) are formed by the intersection of two shear cuts at right-angles. A stud or rivet as claimed in claim 1, characterised in that the shank portion comprises four equispaced legs (15) around the circumference of the stud or rivet, each leg having a sharp point (16). A method of manufacturing a stud or rivet to be welded to a metal container, the method comprising the steps of making at least two intersecting shear cuts (20a,20b) at right-angles to each other through a piece of strip material (18), forming the sheared area into a tubular stud or rivet portion having a plurality of sharp points (16), and removing the stud or rivet from the strip by cutting around the tubular portion thereby to form an annular flanged head portion (12) from which the tubular portion extends.

Inventors: CLARKE ALAN ROY, CLARKE, ALAN ROY
Applicants: PECHINEY PACKAGING FOOD AND GE, PECHINEY PACKAGING FOOD AND GENERAL LINE LIMITED
Application year: 1992
Main classification: F16B19
IPC codes: B23K11, B21D53, B21F45, F16B19