FR2633437A1 - Welding cable with a polyurethane net - Google Patents

Abstract

Cable for carrying high currents, including a central conductor 1 made of stranded copper wires, surrounded by a net 2 and provided with a sealed jacket, inside which a coolant liquid flows, characterised in that the jacket includes, on the one hand, a flexible and sealed inner sheath 8 provided on the inside with a reinforcing braid 7 and, on the other hand, an abrasion-resistant outer sheath 10. Cable resistant to abrasion and bending, used in welding robots.

Description

Welding cable with polyurethane net.

 The present invention relates to a cable for the transport of high intensities comprising a central conductor in copper strands surrounded by a net and provided with a sealed envelope, inside which circulates a coolant.

 Such a cable is described in document FR-A-2 559 # 613-.

 This cable is more particularly intended for supplying the welding electrodes carried by the robots used mainly in the automotive industry. It follows that the waterproof envelope of the cable is subjected to numerous bends and must be able to resist abrasion.

 The cable according to the invention making it possible to greatly improve the resistance to abrasion and to bending is characterized in that the envelope comprises on the one hand, a flexible and waterproof internal sheath provided internally with a reinforcement braid and of on the other hand, an abrasion resistant outer sheath.

 The internal sheath is flexible and waterproof, and it is provided on its internal wall with a reinforcing braid. It is pressed against the net in which the coolant circulates.

The reinforcing braid makes it possible to resist the transverse forces generated by the pressure of the liquid.

 The outer sheath resists bending and abrasion.

 To reduce the weight of this outer sheath while retaining its resistance to folding and abrasion, it is preferably provided with grooves having their rounded edges.

 In order to prevent the reinforcement braid from partially obstructing the openings of the net, the latter can be completely surrounded by a ribbon which can either be laid lengthwise or wound in a helix around the net.

 According to an improvement of the invention an anti-friction layer is arranged between the two sheaths. Thus, one can slide the outer sheath on the inner sheath to release one end and weld a terminal at this end. We can then slide the outer sheath to uncover the second end and weld the second terminal.

 Finally, it suffices to return the outer sheath to its original position to obtain a cable, the outer sheath of which covers the two welded parts of the terminals.

 The invention will now be described in more detail, with reference to a particular embodiment cited by way of nonlimiting example and represented by the accompanying drawings.

 Figure t shows a side view of the central conductor with his net.

 Figure 2 shows the cable with its inner sheath and its outer sheath.

 The central conductor 1 shown in FIG. 1 is made up of one or more strands of copper wire (not shown) and is surrounded by a net 2 of polynrethane made up of ribs deposited in a helix 3 around the conductor 1 and longitudinal ribs 4 deposited on the helical ribs 3. This thread 2 has openings 5 through which the coolant can circulate.

 A method of manufacturing this net 2 is described in document FR-A-2,573,242.

 Around this net 2, a ribbon 6 of synthetic material, for example nylon, is wound (see FIG. 2). On this ribbon 6 is applied a reinforcing braid 7 formed of strands or strands of polyester.

 Then, a flexible and waterproof sheath 8 made of a thermoplastic material such as PVC is extruded around the braid 7.

 The tape 6, the braid 7 and the flexible sheath 8 produce a sealed envelope capable of withstanding the pressure of the water, which circulates along the conductor and through the openings 5 of the net 2. The role of the synthetic tape 6 is prevent the braid 7 and possibly a part of the sheath 8 from obstructing the openings 5 of the net 2 or the longitudinal channels formed by the ribs 4.

 The outer wall of the sheath 8 is then coated with an anti-friction product 9 based on graphite or silicone grease or other equivalent products.

 Then, an external sheath 10 provided with longitudinal grooves 11 with rounded edges is extruded onto the sheath 8. The thickness of the sheath 10 at the bottom of the grooves between the grooves 11 is substantially equal to the height of the grooves.

 When the cable is finished, it is cut into sections of determined length, for example from 2 to 3 meters. I1 then suffices to slide the outer sheath 10, in one direction then in the other, on the inner sheath 8, of about 4 cm in order to be able to solder the electrical connection lugs (not shown) at the ends of the conductor 1, the said lugs being provided with the orifices necessary to create a circulation of water inside the conductor 1 and in the net 2.

Claims (5)

1 / Cable for the transport of high intensities comprising a central conductor (1) in strands of copper wires, surrounded by a net (2) and provided with a sealed envelope, inside which circulates a coolant , characterized in that the casing comprises on the one hand, an internal sheath (8) flexible and sealed internally provided with a reinforcing braid (7) and on the other hand, an external sheath (10) resistant to abrasion.  2 / cable according to claim 1, characterized in that the net (2) is surrounded by a ribbon (6) around which is placed the reinforcing braid (7). 3 / Cable according to one of the preceding claims, characterized in that the external sheath (10) is provided with grooves (11). 4 / cable according to claim 3, characterized in that the grooves (11) are with rounded edges. 5 / Cable according to one of the preceding claims, characterized in that it comprises between the outer sheath (10) and the inner sheath (8) an anti-friction product (9).