JPS59103208A - Cable jacket - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rubber jacket for a cable, in particular an electric welding cable, which is designed to surround a group of electrical conductors and a group of cooling ducts leading to a pressurized medium for cooling. It depends.

In modern automatic welding machines, such as robotic welders, the length of the welding cable is often very short, so that the welding cable is However, flexibility is required.

That is, the cable must be easy to bend and twist.

In addition, this type of cable resists the pressure stresses exerted internally on the cable jacket by the pressurized coolant and by the radial rebound forces caused by the cable cores each time the cable is energized or cut off. Must be able to absorb.

Known welded cable jackets cannot meet all of the above requirements. Rather, due to the short length of the cable, the cable is stiff enough to impede movement of the welding robot, resulting in fatigue failure at bend points in the cable.

It is therefore a first object of the invention to have sufficient flexibility with respect to bending and torsion, even when very short, and to avoid the circles generated in the jacket by the pressure created by the coolant in the cable. It is an object of the present invention to provide a cable jacket capable of absorbing circumferential tensile forces and radial repulsion forces caused by the cable core each time a current is applied or cut through the cable.

To achieve this objective, the cable jacket according to the invention can be of at least one per se known tuft type (
A peripheral reinforcing layer of warp-knit type) is sulfurized into the rubber jacket and one or more unidirectional helical wraps are formed on the radial outside of said reinforcing layer. The reinforcing cord is Japanese-sulfurized, and the spacing between adjacent cord windings is about 2 to 2 in the longitudinal direction of the jacket.
It is characterized in that it has a dimension of 8 mm, preferably about 4 mm. In order to prevent the jacket with warp reinforcement from expanding excessively due to internal pressure and at the same time to have good torsional properties, the cord or cords are wound in a spiral in the same direction; Preferably it is necessary to be located in a single common cylinder radially outside the warp layers in the jacket. Advantageously, each reinforcing cord consists of a slightly twisted polyester thread.

It is also advantageous for the layer of warp reinforcement and the reinforcing cord to be separated in the radial direction by an intermediate rubber layer.

The present invention will be explained in more detail below with reference to the accompanying drawings.

FIG. 1 shows a cross-section of a welding cable 1, which has a rubber outer cable jacket 2 according to the invention. The jacket 2 encloses a conductor group consisting of conductors 3 and 4 of different polarity, arranged in an annular manner and separated in the circumferential direction by rib-like walls 5, which are made of rubber or It protrudes radially from the central object 6 of p'Yc'. The central body 6 has a central coolant duct 7 defining between its outside and the inside of the outer jacket 2 an additional flow duct 8 for passing pressurized coolant, for example cooling water. .

As shown in FIG. 1, the jacket 2 comprises two reinforcing layers 9 of a warp knitted structure, known per se, and one cord spiral winding 10 lying outside these two layers.

In the embodiment, the warp knitting structure is a fabric structure in which knitting yarns, typically filamentary weft yarns, are interwoven in loops with yarns running in the longitudinal direction of the fabric. .

FIG. 2 shows the structure of the jacket according to the invention even more clearly; it only shows one layer of warp reinforcement 9. FIG. Starting from the inside, the jacket 2 comprises a rubber layer 11, a warp reinforcement 9, a thin layer of rubber 12, for example a spirally wound winding of lightly twisted polyester 10, and an outer layer 13 of rubber. are doing. In order to obtain the desired flexibility and strength both in bending and torsion, the jacket is subjected to high external pressures due to the coolant exerted by the cable core each time the cable is energized or disconnected. If a plurality of cords 10 are used, it is important that they run parallel to each other and are wound in the same direction, ie, do not cross each other.

These chords should leave a gap of approximately 2-8, preferably 4, between adjacent chord windings.

Cable jackets according to the invention are preferably made of infinite length by forming on a mandrel, with one or two layers of warp knitted fabric being applied around the inner rubber layer 11. If more than one layer is used, a thin layer of rubber is provided between the layers, and a further thin layer 12 is placed outside the outer warp layer 9. In this case, a single code 1 of the above-mentioned type
0 is helically wound around the layer 12 with a pitch, thus reducing the spacing between adjacent windings of the cord to a standard jacket diameter of about 5-6 cTL, preferably about 2-8 wn1, preferably about 4 mm. It is preferable to do so. Although one single cord is preferred, two or more cords can be wound in parallel in the same winding direction to maintain the above-described spacing of the cord windings. However, this sacrifices some of the good threading properties of the jacket. An outer layer 13 of rubber is then used on the outside of the cord layer, and the jacket components are then bonded together as an integral unit. The outer surface of the jacket is then structured such that its friction is reduced to the desired level.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a welding cable with a jacket according to the invention. FIG. 2 is a cutaway perspective view showing the various layers inside the cable jacket according to the present invention. 2... Rubber jacket 3.4... Electric conductor 6.8... Coolant duct 9.
...Warp knitting reinforcement layer 1o...Reinforcement cord 12...
middle rubber layer

Claims (1)

[Scope of Claims] 1. A welding cable pull jacket designed to surround the electrical conductors (3), (4) and the coolant ducts (6), (8) for conducting the pressurized cooling medium. At least one circumferential reinforcing layer (9) of the warp type is provided with a rubber jacket (
2) that one or more reinforcing cords 01 spirally wound in a single direction on the radially outer side of the reinforcing layer are wrapped around the rubber jacket; The distance between the windings is about 2 to 8 in the vertical direction! A cable jacket characterized in that it has dimensions of: 2 Single or multiple cords constituting the cord reinforcement layer←Q
Jacket according to claim 1, characterized in that the two are arranged in the same cylinder in the jacket (2). 3. A jacket according to claim 1 or 2, characterized in that each reinforcing cord consists of lightly twisted polyester threads. 4. Any one of claims 1 to 3, characterized in that the warp knit reinforcement layer (9) and the reinforcement cord 00 are separated in the radial direction by one intermediate rubber layer (12). The jacket described in.