EP2580764A1

EP2580764A1 - Method for producing a cable and such a cable

Info

Publication number: EP2580764A1
Application number: EP11728208.7A
Authority: EP
Inventors: Jörg Wenzel
Original assignee: Apple Inc
Current assignee: Apple Inc
Priority date: 2010-06-11
Filing date: 2011-06-09
Publication date: 2013-04-17
Also published as: WO2011154507A1; WO2011154507A4

Abstract

The present invention relates to a method for producing a cable comprising a conductor and an insulation surrounding said conductor, in which method a) the conductor is placed between layers of an insulating material, b) excess to the sides of the conductor is cut off, and c) the layers of the insulating material are materially bonded to one another. The present invention also relates to a cable comprising a conductor which is placed between layers of an insulating material, laterally protruding insulating material being cut off and the layers of the insulating material being materially bonded to one another, so that the conductor is surrounded by an insulation.

Description

Method for producing a cable and such a cable

The invention relates to a method for producing a cable and such a cable.

Such cables are typically comparatively thin cables having an outer diameter preferably in the range of one to a few millimeters (e.g., 1.5 mm to 3.5 mm) having an internal electrical conductor and an insulation (cable sheath) surrounding the conductor. The conductor is for example a wire, stranded wire, or a stranded individual strand and preferably already has a conductor insulation. The cable preferably has a plurality of such conductors.

In particular, it is visible in use cables in the electronics and / or household sector.

Such cables are usually produced in the extrusion process. Such an extrusion process makes certain demands on the insulating material used, so that not all materials are suitable for extrusion. Also can be designed with the extrusion process only certain cable shapes, usually only rotationally symmetrical configurations.

The invention has for its object to provide an alternative manufacturing process, as well as a cable manufactured thereafter.

The object is achieved according to the invention by the features of

Claim 1 and by a cable having the features of claim 23.

Preferred developments are given in the dependent claims.

In the method according to the invention it is provided that the conductor is first inserted between layers of an insulating material, and that subsequently - if necessary - laterally projecting insulating material is cut off if necessary and the layers of the insulating material to each other

Formation of an insulation of a cable sheath with each other in particular materially connected. Preferably, this is a tool shape used, in which the conductor is inserted together with the layers of insulating material. The tool mold is preferably a mold with two halves, between which the conductor is inserted with the layers and pressed.

In this context, material connection is understood in particular to mean a fusion or crosslinking of the material at the boundary layer of the two layers, so that in the original region of the boundary layer a homogeneous

Material structure exists without separating layers. The material of the two layers is in particular identical, so that by materially connecting the

Material structure in the original area of the boundary layer (at least in the interior of the cable sheath) is indistinguishable.

Preferably, the tool mold comprises a recess into which the conductor is inserted, so that the course of the cable is defined by the depression. Preferably, a recess is in both tool halves

(symmetrical) provided.

The mold is preferably designed such that during

Compress immediately the desired separation of the protruding insulating material takes place. For this, the tool shape along a desired cutting line, in particular along the depression, with a separation or

Cutting device, in particular a cutting or cutting edge equipped.

As material for the layers of the insulating material in particular an elastically or plastically deformable starting material is used, which by treatment, for example thermally or by a chemical reaction, together to form the insulation material, for example, by

Meld or merge connect. Preferably, a thermoplastic such as PP or PE is used as the material, which is preferably crosslinkable. Alternatively, a rubbery material, in particular a silicone rubber is used. The material connection takes place in particular by a crosslinking reaction (curing). This is preferably thermally activated and in particular within the mold. Alternatively it can also be provided to carry out the curing outside of the mold. The crosslinkable starting material is preferably one One-component system, therefore, no material mixtures are required to start the crosslinking reaction.

The cable produced by this method is usually an elongated, in particular branched cable, in which the cable length is a multiple of the cable diameter, preferably more than 200 times. Branched cables are partially manufactured in injection molding processes by placing a prefabricated conductor bundle into a corresponding one

Injection mold or other mold is inserted and then the insulating material of the cable sheath is poured or injected into the tool mold. In the case of the very thin and

elongated cable is such a method by casting or injection molding but not or only with great effort possible. At least a plurality of pouring / injection points are required. However, this is not desirable for design reasons.

For easier demolding and / or to create a special

Surface and design structure is in a preferred variant in the

Tool mold introduced the surface of the insulating material influencing element. This element may be a powder material, e.g. Mica.

To the most efficient manufacturing process with the lowest possible

To allow material scrap is provided in an expedient development that the individual layers, at least one layer, are preformed according to the desired cable design. The layers therefore already have a desired negative shape and are designed in the manner of shell halves, wherein the two shell halves connect to the tubular structure of the desired cable sheath in the further course of the process.

Between the two respective "shell halves" the ladder are inserted. The preformed layers or shells usually have a thickness in the mm range. In this respect, therefore, these are preformed, structured or embossed films, preferably of a thermoplastic material.

Generally, the cable is provided that the material thickness of the insulation and thus of the cable sheath over the length of the cable varies and assumes different thicknesses and / or different cross-sectional shapes. Herein lies a particular advantage of this batch process compared to a continuous extrusion process, namely that over the cable length varying configurations of the cable sheath are readily possible, which differ in terms of cross-sectional area and / or material thickness.

It is expediently provided that the preformed layers already show these variations over the length of the cable, that is to say they have varying thicknesses. In particular, it is provided in this case that at least to one end side is preferably provided to all end sides of the cable, a change in shape, in particular a thickening.

The cable is preferably a cable with a branched structure, for example in the manner of a cable harness with a plurality of cable ends. In particular, the cable bifurcates and expediently forms a Y-structure. The cable is in this case used in particular for a headset, in particular with stud earrings, as it is used for many especially portable small electrical appliances such as mobile phones, MP3 players, or other mobile playback devices. Especially with these devices, design aspects are very important. By the special described here

Manufacturing method for such a cable, in particular headphone cable, with branched structure, it is possible to create such a headphone cable as a "cast" with a high appealing design.

According to an expedient development it is provided that in

Branching point a particular U-shaped separating element is inserted for separating the conductor. Expediently, it is furthermore provided that the conductors are fastened and tensioned at their end points when they are inserted into the tool mold. Due to the U-shaped separating element, the particular advantage is achieved that the two branched conductors can be defined and guided very close to one another. Preferably, it is provided that the two conductors are continued at least substantially in parallel at a small distance of, for example, a few millimeters. As a result, the necessary width for the layers (preformed films) is kept as low as possible, so that the material waste is kept low during manufacture. In order to be able to produce the preformed layers as inexpensively as possible and in a simple process, a structured embossing or shaping roller is provided, via which a continuous film in particular is continuously guided and thereby brought into the desired preformed embossing. In this case, the embossing roller is preferably already supplied with a film having a film thickness varying over the length of the roller, so that overall the smallest possible degree of deformation of the film itself is required. This can be high

Process speeds are set. Conveniently, the cable longitudinal direction extends longitudinally of the roller, i. the embossed structure for producing the preformed film is not impressed in the circumferential direction of the roller but in the longitudinal direction thereof. The length of the roller therefore corresponds at least to the length of the desired cable (for example in the range of 1 to 2 m).

In the sense of a uniform and compact design "from a cast" is further provided that at the end of the ladder already an electrical functional element, in particular contact plug, in the case of a headphone, for example, a jack, struck or connected, which in the formation of the cable sheath surrounded by the two layers of insulating material. The cable sheath is therefore seamless and homogeneous in the insulating sheath of the electrical functional element over. In principle, it is possible to strike at all ends already the desired required electrical functional elements, in the case of a headphone, these would therefore be the corresponding speaker units. At the same time thereby the advantage of a reliable seal between the actual cable and the functional element connected thereto is achieved. In summary, therefore, the invention relates in particular to the production of a particular branched cable with an insulation of two material together by means of a mold in a discontinuous process associated insulating layers.

The particular advantage of this discontinuous method is the fact that many design degrees of freedom for the design of the cable allows and the cable can be freely designed in a wide range, especially with over the length of the cable varying wall thicknesses of the insulation. Also, the material is freely selectable within wide limits, which is also special among design aspects is advantageous. It is therefore made possible by this method, the production of a cable with special design effects.

In particular, the cable is a cable for electrical or electronic equipment in which the cable is visible. Preferably, it is intended for electric and in particular mobile playback devices (picture / sound) and in particular designed as a headphone cable. However, the method described here can in principle be transferred to all other cables in which a special cable design is desired. Further applications are therefore, for example, the supply cables of household electrical appliances that impose a special design claim.

An embodiment will be explained below with reference to FIGS. The figures with the explanations contained therein are self-explanatory.

Fig. L to 5 show in a schematic, simplified perspective

Representations of individual steps of the method in a simple embodiment, wherein FIG. 3 shows a branched headphone cable in a schematic plan view,

FIG. 7 shows in a greatly simplified manner a pre-structured foil / layer, FIG.

Fig. 8 shows in a highly simplified schematic perspective

Represent an embossing roll for forming the preformed film shown in Fig. 7 / position and

Fig. 9 shows greatly simplified around a separator guided around ladder.

Figures 1 to 5 show an example of the production of a cable. Fig. 1 shows a bottom plate 7 of a mold. The lower plate 7 has cutting edges 13 and a recesses 9. The depressions 9 has a branch 11. In the lower plate 7, a layer 3 of insulating material, the so-called

Base layer, inserted. This layer 3 may be sheet-shaped or e.g. be preformed in the cross-section half-round.

FIG. 2 shows how the conductor 1 is inserted into the lower plate 7 designed with insulating material 3. The conductor 1 may be a simple wire or made of stranded wires. The conductor 1 is by means of suitable devices 17 tightened and can also be biased. It can also be another coaxial cable inserted.

FIG. 3, like the so-called cover layer, shows a further layer 5

Insulating material is placed on the conductor 1 and the base layer. The cover layer can be made of the same material as the base layer, or of another material. This layer 5 may be sheet-shaped or e.g. in the

Cross-section preformed semi-circular. It is also possible to insert additional layers, e.g. for shielding the cables or as protection against environmental influences. It is also possible to introduce various additives, e.g. for a better one

Demolding or for producing certain surfaces (effects).

Figure 4 shows the closing of the mold by placing a top plate 15. The top plate 15 may also have recesses for the conductor 1. But bottom and top plate 7, 15 can also be one-piece, e.g. be formed with a hinge. Lower and upper plates 7, 15 are pressed against each other and preferably heated. By pressing together the lower and upper plates 7, 15, the over the conductor 1 in all directions protruding insulating material 3, 5 is separated. The heating leads to a material connection of the layers 3, 5 of the insulating material by e.g. Merge and / or crosslink.

Figure 5 shows the opening of the mold 7, 15, the removal of the remaining material sections 3a, 3b, 3c and the "finished" cable.

For producing a cable according to FIGS. 1-5, a lower and upper plate 7, 15 (with the incorporated shape) are therefore required. At the

Manufacturing process is placed on the lower plate 7 a layer (layer 3) of the insulating material, similar to a dough layer during baking. In the second step, for example, stranded cores 1 (conductor with conductor insulation) are clamped in the mold and then covered in another with a cover layer 5 (second layer) of the insulating material. When closing the mold with the top plate 15, the excess insulating material 3a, 3b, 3c is cut off and the remaining material is pressed into the desired shape. To cure the product, the mold is heated to the crosslinking process

complete. As an alternative to the use of smooth, even layers (base layer 3, cover layer 5) of the insulating material (in particular thermoplastic material) preformed, structured layers 6 are taken, which are joined together in the manner of particular half-shells. An example of this is shown in FIG. 7. This preformed layer 6 in this case has in particular material thickening 8 in the end regions and / or in nodes at branching points 11. In this way, both the material thickness, as well as the cross section of the cable (round, flat, etc.) can be varied.

The length of the layers 3, 5, 6 corresponds generally to at least the total length of the cable (at least as far as the cable sheath extends), as shown in Fig. 6. Preferably, the layer 3, 5, 6 at the same time also covers a contact plug 10 which is already end-hinged, for example a jack plug, so that the cable jacket also seamlessly covers this contact plug 10. In the headphone cable shown in Fig. 6, only the contact plug 10 is integrated, the actual headphone speakers are still to be connected in a conventional manner with the conductors 1 and the cable ends.

These preformed layers 6 are preferably produced in a continuous production process by means of a structure or embossing roller 12 shown in FIG. 8. The roller 12 has, on its outer surface, as can be seen in Fig. 8, a survey 14 which substantially in

Longitudinal direction of the roll longitudinal axis and the desired cable structure, in particular a branched structure maps. Distributed over the circumference of the roller 12 in this case preferably a plurality of such elevations or structures 14 are formed.

When inserting the conductor 1 in the mold is preferably on the

Junction point 11 a particular U-shaped separator 16 inserted and the individual conductors 1 are guided around this separator 16 around, as shown in Fig. 9 is greatly simplified. By the

Separator 16, the conductors 1 are securely separated, which allows a close and space-saving Aneinenderlegen the conductor 1.

The method described here is particularly complex

Cable structures with branches 11 and at least three cable ends applied. In principle, this method also offers the possibility of producing complex hose structures with branches. In this case, a forming core is preferably inserted instead of the conductor, which is removed after the connection of the two layers again.

Claims

claims

Method for producing a cable having a conductor (1) and an insulation surrounding it, in which

a. the conductor (1) is inserted between layers of an insulating material (3, 5),

b. insulating material (3, 5) protruding laterally of the conductor (1)

is cut off, and

c. the layers of the insulating material (3, 5) materially together

get connected.

Method according to Claim 1, in which the conductor (1), together with the layers of the insulating material (3, 5), is inserted into a tool mold (7, 15) and at least one, preferably both, of the method steps b, c in / with the mold ( 7, 15) are executed.

A method according to claim 1, wherein the layers of insulating material (3, 5) are joined together by a melting or crosslinking process.

Method according to one of the preceding claims, in which the crosslinking process of the layers (3, 5) takes place at least partially after the removal from the mold (7, 15).

Method according to one of the preceding claims, in which the tool mold (7, 15) has a recess (9) corresponding to the desired course of the cable, which in particular also

Branching (11).

Method according to one of the preceding claims, wherein the tool mold (7, 15) is a two-part mold.

Method according to one of the preceding claims, wherein the tool mold (7, 15) along a desired cutting line, in particular along the recess (9), a separating or

Cutting device (13), in particular a separating or cutting edge has.

Method according to one of the preceding claims, in which the material connection takes place by thermal treatment, in particular the tool mold (7, 15) is heated.

Method according to one of the preceding claims, in which a crosslinkable starting material is used as the material for the layers (3, 5), and the crosslinking process takes place by means of a crosslinking which is in particular thermally activated.

Method according to one of the preceding claims, in which the material of the layers (3, 5) in the initial state is plastically or elastically deformable.

Method according to one of the preceding claims, in which the material of the layers (3, 5) is optionally a thermoplastic such as PP or PE and / or an elastomer such as silicone rubber.

Method according to one of the preceding claims, in which the cable length is a multiple of the cable diameter, in particular more than 200 times, preferably more than 500 or 1000 times.

Method according to one of the preceding claims, in which an element influencing the surface of the insulating material (3, 5), in particular powdery material such as mica, is introduced into the mold (7, 15) and / or an element improving the mold release behavior.

Method according to one of the preceding claims, in which the layers (3, 5) are already preformed according to the desired cable design (negative mold (6), preformed films). Method according to one of the preceding claims, in which the material thickness of the layer (3, 5) varies over the length of the conductor (1).

Method according to one of the preceding claims, in which at least to one end side of the cable this has a change in shape, in particular a thickening (8).

Method according to one of the preceding claims, in which the cable has a branched structure (11) and in particular forks (Y-structure).

Method according to one of the preceding claims, in which at the branching point a particular U-shaped separating element (16) for separating the conductors (1) is inserted and the conductors (1) are preferably tensioned.

Method according to one of the preceding claims, in which the conductors (1) run at least substantially parallel to the branching point.

Method according to one of the preceding claims, wherein the layers (3, 5) with the aid of a particular structured (embossing) roller (12) are produced.

Method according to one of the preceding claims, in which the intended conductor run in the preformed layer (6) extends at least approximately along the roll axis.

Method according to one of the preceding claims, wherein the end of the cable, an electrical functional element, such as a contact element, in particular a contact plug (10) is provided, which is also inserted between the layers (3, 5, 6), so that these transition-free as well form the sheath of the contact element.

Cable comprising a conductor (1) interposed between layers of a

Insulating material (3, 5) is inserted, wherein the side of the conductor (1) projecting insulating material (3, 5) is cut off, and the layers of the insulating material (3, 5) are materially interconnected, so that the conductor (1) is surrounded by insulation.

Cable according to claim 23, wherein the material thickness of the layer (3, 5) varies over the length of the conductor (1).

Cable according to one of the preceding claims, comprising a branched structure (11) and in particular forked (Y-structure).