Bus bar with terminal lugs

Abstract

 A bus bar is described which may be made of copper strip in a U-shaped cross section. Terminal lugs (3a, 3b) for use with spade connectors are integral with the bus bar and are punched in the web (1) and subsequently bent inwards into the space between the side flanges (4a, 4b) in the U-shaped cross section.

Description

[0001] The invention relates to a sectional bus bar with terminal lugs for spade connectors comprising a web and side flanges.

[0002] Bus bars normally consist of sectional copper or aluminium bars onto which terminal lugs have been fixed for use with connectors. In many instances such bus bars have to resist forces of both a mechanical and an electrical nature, e.g. in the case of unintentional short circuits. In order to simplify the manufacture of such bus bars, the said terminal lugs can be punched or stamped in the bus bar proper. If the bus bar consists of sheet metal which by itself has only little rigidity, then it may be still further weakened by the punching of terminal lugs. If, on the other hand, the bus bar is sectional, by punching the terminal lugs in the bus bar in a suitable manner any appreciable weakening may be avoided.

[0003] It is known, for example from Danish printed application 134,378, Danish Publicly Available application 3983/76, and US Patent 3,210,716, to use bus bars which are essentially U-shaped in cross section. It is also known, for example from German AS 1,909,166 and US Patent 3,902,778, to stamp terminal lugs for spade connectors in flat, rectangular bus bars. It has not, however, previously been suggested to combine these different methods of manufacture of a bus bar.

[0004] An object of the invention is to provide a construction which combines the advantages of known constructions in such a way that the bus bars acquire sufficient rigidity, at the same time as saving material by reducing the gauge of material required. Furthermore, special clamping provisions for branching may be avoided, thereby reducing the manual work needed when making installations inside cabinets.

[0005] These advantages are gained in a bus bar according to the invention, which is characterised by terminal lugs punched in the web of the sectional bus bar.

[0006] The bus bar according to the invention may be further characterised in having a U-shaped cross section and in that the terminal lugs are bent inwards from the web. In this manner a bus bar is obtained which is only slightly reduced in strength as compared with a similar bus bar without punched terminal lugs. At the same time a compact construction is obtained, since the connectors are disposed in the space between the side flanges. Furthermore, the bus bar according to the invention may be characterised in that the free ends of the side flanges in the U-shaped section may be bent so as to obtain a still more rigid construction.

[0007] The invention is to be described more fully with reference to the drawing, in which:-

Fig. 1 shows part of a bus bar according to the invention and having a U-shaped cross section viewed into the hollow space,

Fig. 2 shows the same in a side view,

Fig. 3 shows a cross section at III-III in Fig. 1,

Fig. 4 shows a system of bus bars according to the invention mounted in a frame and viewed from below,

Fig. 5 shows a simpler embodiment of the invention viewed from one end,

Fig. 6 shows the same as Fig. 5, but with the terminal lugs bent outwards,

Fig. 7 shows a bus bar according to the invention having an H-shaped cross section and viewed from one end, and

Fig. 8 shows a bus bar with a U-shaped cross section and with the ends of the side flanges bent outwards.

[0008] Fig. 1 shows the web 1 in which a hole 2 is drilled or punched for mounting the bus bar onto a frame or similar, and two terminal lugs 3a and 3b. These terminal lugs 3a and 3b are bent inwards into the space between the side flanges 4a and 4b at an angle of approx. 45° with respect to the web 1, which may be seen most clearly in Fig. 2. As is common in terminal lugs for spade connectors, the lugs 3a and 3b are provided with small holes 5a and 5b. In Fig. 3 it can be seen that the ends 6a and 6b of the side flanges 4a and 4b are bent inwards at right angles.

[0009] An example of three bus bars according to the invention disposed in parallel is shown in Fig. 4. The bus bars are fixed to a frame 7 by means of screws 8. The various parts of the bus bars are numbered in the same manner as above.

[0010] The cross section of the bus bar shown in Fig. 5 differs from the cross sections shown in Figs. 1 - 4 in that there are no bent-in flange ends.

[0011] The cross section of the bus bar shown in Fig. 6 has the terminal lugs (3a') bent outwards, which means that the best way of attaching this bus bar to a frame 7 is by means of screws through the side flanges 4a or. 4b. The same applies for the bus bar having an H-shaped cross section shown in Fig. 7.

[0012] The ends 6a' and 6b' of the side flanges 4a and 4b may be bent outwards as in Fig. 8. This is used where a maximum of space is needed around the terminal lugs 3, while retaining the rigidity derived from the bent ends of the side flanges.

[0013] A feature which is common to the bus bar cross sections shown in Figs. 1 - 6 and Fig. 8 is that the bus bars according to the invention may conveniently be manufactured by folding and punching copper or aluminium strip in a manner which is well-known in metalworking.

Claims

1. A sectional bus bar with terminal lugs (3a, 3b) for spade connectors comprising a web (1) and side flanges (4a, 4b), characterised in that the terminal lugs (3a, 3b) are punched in the web (1) of the sectional bus bar.

2. A sectional bus bar as claimed in claim 1, characterised in that it has a U-shaped cross section and that the terminal lugs (3a, 3b) are bent inwards from the web (1).

3. A sectional bus bar as claimed in claim 1, characterised in that it has a U-shaped cross section and that the terminal lugs (3a') are bent outwards from the web (1).

4. A sectional bus bar as claimed in claim 2 or 3, characterised in that the ends (6a, 6b) of the side flanges (4a, 4b) in the U-shaped cross section are bent inwards.

5. A sectional bus bar as claimed in claim 2, characterised in that the ends (6a', 6b') of the side flanges (4a, 4b) in the U-shaped cross section are bent outwards.

6. A sectional bus bar as claimed in claim 1, characterised in that it has an H-shaped cross section.

Drawing