Device for locally flaring a braided tubular structure

A device for flaring an end section of a braided tubular structure of an electrical conductor defines a reception volume having a peripheral boundary for receiving the end section of the braided tubular structure. The device further includes one or more rotatable rollers of which each has at least one peripheral roller surface facing the peripheral boundary of the reception volume. The one or more rollers are adapted to move relative to the reception volume in a peripheral direction about the reception volume for flaring the end section.

CROSS-REFERENCE TO RELATED APPLICATIONS

FIELD OF THE INVENTION

The present invention relates to a device for flaring braided tubular structures, and more specifically, to a device for flaring a shield of one or more electrical conductors.

BACKGROUND

Numerous applications in the field of automotive engineering and in other technical fields rely on data being transmitted in the form of electrical signals via electrical conductors acting as a signal path for the electrical signals. To ensure sufficient signal transmission quality, shielded coaxial cables are usually deployed. Typically, the electrical conductors constitute a center core and are circumferentially surrounded by a tubular shield made from braided strands of copper wire or other kinds of metal wire. The shield functions based on the principle of a Faraday cage, protecting the electrical signals from external electrical noise and preventing the electrical signals from causing electromagnetic interference within surrounding components. In order to prevent direct contact of the electrical conductors with the shield, a dielectric insulator is interposed in between. Optionally, a layer of metal foil e.g., aluminum foil, may be situated between the dielectric insulator and the shield, the metal foil reflecting back internal and external electromagnetic radiation according to the so-called mirror effect.

At the source and/or destination of the electrical signals, suitable interfaces, such as plug connectors, may be used to connect the electrical conductors with components upstream and/or downstream of the signal path. In the case of shielded coaxial cables, the shield is radially distanced from the center core and the dielectric insulator is partially removed to make the center core accessible. Further, the shield needs to be connected to the interfaces, e.g., to a ground contact of the interface, in order to be effective. In certain applications, removal of the metal foil is necessary prior to the connection of the shield to the interface.

Accordingly, there is a need for improved devices and associated methods for evenly and effortlessly flaring the shield, preferably without damaging the strands of the shield itself and the metal foil.

SUMMARY

In one embodiment of the present disclosure, a device for flaring an end section of a braided tubular structure of an electrical conductor is provided. The device defines a reception volume having a peripheral boundary and which is adapted to receive the end section of the braided tubular structure. The device further includes one or more rotatable rollers of which each has at least one peripheral roller surface facing the peripheral boundary of the reception volume. The one or more rollers are adapted to move relative to the reception volume in a peripheral direction about the reception volume for flaring the end section.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Technical solutions of the present disclosure will be described hereinafter in detail through embodiments and with reference to the attached drawings. In the specification, the same or the like reference numerals refer to the same or the like elements. The illustration of the embodiments of the present disclosure made with reference to the attached drawings is aimed to explain the general inventive concept of the present disclosure, not to be construed as a limitation of the present disclosure.

In the following, the structure of possible embodiments of a device1for flaring an end section2of a braided tubular structure4, such as a shield6of an electric conductor8or cable10, according to the present invention is explained with reference to the exemplary embodiments shown inFIGS.1through6. Further,FIGS.1through6are used for explaining the associated methods according to the present invention.

FIG.1shows a perspective view of the device1according to one possible embodiment of the present disclosure, the device1defines a reception volume12which has e.g., a cylindrical, peripheral boundary14and is adapted to receive the end section2of the braided tubular structure4. In particular, the reception volume12may be defined in such a way that the peripheral boundary14of the reception volume12preferably exactly coincides with an outer circumferential surface16of the braided tubular structure4once the end section2of the braided tubular structure4is received within the reception volume12.

The device1may further comprise one or more rollers18of which each has at least one peripheral roller surface20(seeFIG.3) at least partially facing the peripheral boundary14of the reception volume12and each is adapted to move relative to the reception volume12in a peripheral direction22about the reception volume12. Upon definition of the reception volume12, the one or more rollers18may be specifically adapted to trace the peripheral boundary14of the reception volume12. In particular, the one or more rollers18may move relative to the reception volume12in the peripheral direction22, while the at least one peripheral roller surface20of each of the one or more rollers18borders the peripheral boundary14of the reception volume12.

Because the outer circumferential surface16of the braided tubular structure4coincides with the peripheral boundary14of the reception volume12, the one or more rollers18may engage in rolling contact with the outer circumferential surface16of the braided tubular structure4received within the reception volume12. When the one or more rollers18roll over the outer circumferential surface16of the braided tubular structure4at the end section2of the braided tubular structure4, individual strands of the braided tubular structure may successively be untangled. This gradually leads to the intended flaring of the braided tubular structure4, while only minimal to no normal force is exerted on the outer circumferential surface16of the braided tubular structure4.

InFIG.1, the device1is shown with exactly one roller18. This embodiment may be utilized when the to-be-flared braided tubular structure4is relatively stiff and may support its own weight as well as any normal force exerted on the outer circumferential surface16of the braided tubular structure4by the one roller18.

According to the geometric dimensions and material characteristics of the to-be-flared braided tubular structure4, additional stabilization may be necessary. For this stabilization, the device1may comprise more than one e.g., two, three, four, five, six or even more rollers18. As exemplarily shown inFIGS.2through6, the device1may comprise three rollers18.

Hereinafter and for the sake of brevity, when referring to each roller18, it shall be understood that each of the one or more rollers18is meant, unless specified otherwise. Accordingly, when referring to all rollers18, it shall be understood that all of the one or more rollers18are meant, unless otherwise specified.

As can be seen fromFIGS.2and3, each roller18may have a roller axle24extending coaxially with a symmetry axis26of the respective roller18. Each roller18may be adapted to rotate about its roller axle24. In the shown embodiment ofFIG.3, the roller axle24of each roller18is a rotating axle28monolithically connected with the respective roller18and protruding therefrom as cylindrical projections30. Alternatively, the roller axle24may be a stationary axle penetrating the respective roller as a separate structural element. In both cases, the roller axles24may be utilized to rotatably hold the respective roller18in the device1. It is to be understood that the term axle also covers pins, shafts and other types of fixed beams with bearings at their ends about which the respective roller18may be adapted to rotate.

In another alternative embodiment, the roller axles24may be constituted by imaginary axes merely defining an orientation of the roller's rotation. The device may comprise at least one cage (not shown) for rotatably holding each roller18in such an embodiment.

The roller axles24of all rollers18may be parallel to each other. Alternatively, all roller axles24may be arranged in a conical configuration i.e., all roller axles24may be distributed, preferably evenly, on a surface of an imaginary conical shape (not shown).

Further inFIG.3, it can be seen that the at least one peripheral roller surface20of each roller18may extend about the symmetry axis26and subsequently also about the roller axle24of the respective roller18. Preferably, the at least one peripheral roller surface20of each roller18may continuously extend in a circumferential direction31with respect to the roller axle24of the respective roller18forming a closed, rotationally symmetrical surface32.

Still referring toFIG.3, each roller18is shaped as a disc34, wherein the at least one peripheral roller surface20corresponds with a peripheral surface36of the disc34. As is further shown, the at least one peripheral roller surface20of each roller18is convexly formed having an equatorial line38extending on a plane perpendicular to the roller axle24of the respective roller18. Alternatively, the one or more rollers18may also have a cylindrical, spherical, conical or any other rotationally symmetrical shape.

As is indicated inFIG.4, each roller18may be adapted to revolve around the reception volume12about an axis of revolution40. The axis of revolution40may extend through the reception volume12, preferably coaxially with a center line42of the reception volume12. In particular, each roller18can thus be moved along a circular path in a tangential direction respect to the braided tubular structure4when the braided tubular structure4is received within the reception volume12.

More specifically, the device1may comprise at least one spindle44(seeFIG.1) having a rotational axle46extending coaxially with the axis of revolution40. The device1may further comprise a rotational drive48adapted to move each roller18, preferably automatically, in the peripheral direction22about the reception volume12. In particular, the rotational drive48may turn the at least one spindle44.

Each roller18may be mounted, preferably slidably, on the at least one spindle44and spaced apart from the axis of revolution40(seeFIG.2). Here, the axis of revolution40may be configured parallel to the roller axle24of each roller18. Alternatively, the roller axle24of each roller18may be oblique with respect to the axis of revolution40.

At least two rollers18of the device1may be held at an adjustable distance50from one another (seeFIG.2), the distance adjustment being possible prior to and during operation of the device1. The device1may further comprise a distance control unit52for manipulating and controlling the adjustable distance50between the at least two rollers18held at the adjustable distance50.

At least one roller18of the device1may be adapted to move in a radial direction54with respect to the reception volume12. Thereby, the respective roller18can be moved away from the reception volume12in order to clear access to the reception volume12. This facilitates the insertion of the end section2of the braided tubular structure4into the reception volume12.

Once the end section2of the braided tubular structure4is received within the reception volume12, the respective roller18can be moved towards the reception volume12and brought into contact with the outer circumferential surface16of the braided tubular structure4. For this, the at least one spindle44may comprise a cylindrical chuck56, which is attached to an end58of the at least one spindle44. On a front face60of the cylindrical chuck56at least one jaw62may be slidably mounted, wherein each roller18is rotatably mounted on the at least one jaw62. Particularly, the at least one jaw62may be oriented to move each roller18radially relative to the reception volume12.

As is indicated inFIGS.2and4with dashed arrows101, preferably all rollers18are adapted to move in the radial direction54. Accordingly, the device1may comprise at least two jaws62arranged oppositely with respect to the reception volume12on the front face60of the cylindrical chuck56. Each roller18may be rotatably mounted on one of the at least two jaws62, wherein the distance64between the at least two jaws62may be adjustable e.g., by means of the above distance control unit52.

In an embodiment of the device1comprising three rollers18, the above distance control unit52may be utilized to manipulate and control the distance66(seeFIG.5) between the reception volume12and the at least one peripheral roller surface20of the respective rollers18in such a way that the three rollers18may have their respective roller axles24each extend through one corner of an imaginary isosceles triangle68before distance adjustment (seeFIG.4). After distance adjustment, the three rollers18may have their respective roller axles24each extend through one corner of an imaginary equilateral triangle (not shown).

Moving toFIG.5, it can be seen that in a cross-section of the reception volume12, the cross section being perpendicular to the center line42of the reception volume12, the reception volume12may exhibit a closed circumference70. Each roller18may be adapted to move relative to the reception volume12along a segment of the closed circumference70of the reception volume12. Alternatively, each roller may be adapted to move relative to the reception volume12along the entire closed circumference70of the reception volume12.

As further shown inFIG.5, the three rollers18may be distributed in a circular arrangement around the reception volume12. In the shown circular arrangement, each point on the at least one peripheral roller5surface20of the respective roller18, which is most proximal to the reception volume12, is situated on an imaginary circle72surrounding the reception volume12. Preferably, the imaginary circle72coincides with the above closed circumference70of the reception volume12and/or the three rollers18are evenly distributed on the imaginary circle72. The even distribution on the imaginary circle72of the three rollers18corresponds with the configuration described above where the three rollers18may have their respective roller axles24each extend through one corner of the equilateral triangle (not shown). Alternatively, in an embodiment of the device1with two rollers (not shown), the two rollers may be arranged on opposite sides of the reception volume12. In an embodiment of the device1with a higher even number of rollers, the rollers may be pairwise arranged on opposite sides with respect to the reception volume12

On at least one jaw62, at least two rollers18may be rotatably mounted (seeFIGS.3to5). Optionally, a distance74between the at least two rollers18may be adjustable prior to and during operation of the device1e.g., by means of the above distance control unit52. This is exemplarily indicated by dashed arrows76inFIG.5. In particular, the at least one jaw62may be constituted by two separate halves78a,78b, which are movable relative to each other.

Referring again toFIGS.1and2, the device1may further comprise a displacement mechanism80for guiding a relative movement82between the reception volume12and each roller18. The relative movement82is preferably a translational movement84parallel to the center line42of the reception volume12. In this way, the relative movement82may take place in an axial direction86with respect to the reception volume12and the braided tubular structure4received within the reception volume12. In particular, the displacement mechanism80may comprise a linear slider88on which all rollers are mounted, directly or indirectly. Further, the displacement mechanism80may comprise a linear drive90adapted to move each roller18, preferably automatically, relative to the reception volume12e.g., in the axial direction86with respect to the reception volume12.

The device1may further comprise at least one holding mechanism92adapted to e.g., temporarily fixate the braided tubular structure4relative to each roller18and adapted to position the end section2of the braided tubular structure4within the reception volume12, preferably coaxially with the reception volume12(seeFIG.2). As is depicted inFIG.5, the at least one holding mechanism92may be constituted by at least two clamps94, which mechanically clasp the braided tubular structure4therebetween. Further, the holding mechanism may comprise a funnel like structure96having a narrower opening98, which faces towards the at least two clamps94, and a wider opening100, which faces away from the at least two clamps94. Instead of the one or more rollers18, the at least one holding mechanism92may be mounted on the linear slider88of the displacement mechanism80described above.

As is indicated by a set of dashed arrows102inFIG.6, the device1may be adapted to simultaneously move each roller18in the peripheral direction22about the reception volume12and in the axial direction86with respect to the reception volume12, so as to move each roller18along a spiral or helicoidal path104around the reception volume12. For this, an electrical control unit106may be provided in the device1for synchronizing the movement of the rotational drive48and the linear drive90.

A method for locally flaring an end section2of a braided tubular structure4, such as a shield6of an electric conductor8or cable10according to the present invention will be explained in reference toFIGS.1through6. The method comprises the step of rolling with one or more rollers18over an outer circumferential surface16of the braided tubular structure4at the end section2of the braided tubular structure4, preferably so as to successively untangle strands of the braided tubular structure4and gradually flare the end section2of the braided tubular structure4. This step is depicted inFIG.1.

As shown inFIG.1, the method may comprise, optionally and prior to the above rolling step, the step of securing the braided tubular structure4, preferably by means of at least one holding mechanism92, the step of positioning the end section2of the braided tubular structure4within a reception volume12and the step of moving the one or more rollers18to a position bordering the reception volume12. Moreover, in the above rolling step, each roller18may be moved relative to the reception volume12in a peripheral direction22about the reception volume12. Preferably, the above positioning step, moving step and rolling step may be conducted within a cycle time of less than five seconds.

Subsequent to the above rolling step, the method may comprise the step of adjusting a relative position between each roller18and the braided tubular structure4received within the reception volume12, such that each roller18is radially aligned with an un-flared section108of the braided tubular structure4. The un-flared section108of the braided tubular structure4is characterized in that it is a section where the one or more rollers18have not yet rolled over. For example, the un-flared section108of the braided tubular structure4may be adjacent to the end section2of the braided tubular structure4. This adjustment step is depicted inFIG.2by dashed contour lines110of each roller18symbolizing the location into which the respective roller18will be moved subsequently.

The above adjusting step may be followed by the step of rolling with each roller18over the outer circumferential surface16of the braided tubular structure4at the un-flared section108of the braided tubular structure4. Herein, the one or more rollers18may be moved in the same direction as depicted inFIG.1or in the opposite direction.

Optionally, the above adjusting step and rolling step may be repeated until a length112(seeFIG.6) and/or degree of flaring at the end section2of the braided tubular structure4satisfactorily meets the required specifications of the respective application.

FIG.6shows an alternative embodiment of the inventive method, wherein the end section2of the braided tubular structure4may be flared over the length112by moving each roller18in an axial direction86with respect to the braided tubular structure4during the above rolling step. Thus, each roller18follows a spiral or helicoidal path104with respect to the braided tubular structure4.

It should be appreciated by those skilled in this art that the above embodiments are intended to be illustrative, and many modifications may be made to the above embodiments by those skilled in this art, and various structures described in various embodiments may be freely combined with each other without conflicting in configuration or principle.

Although the present disclosure have been described hereinbefore in detail with reference to the attached drawings, it should be appreciated that the disclosed embodiments in the attached drawings are intended to illustrate the preferred embodiments of the present disclosure by way of example, and should not be construed as limitation to the present disclosure.

Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

It should be noted that, the word “comprise” doesn't exclude other elements or steps, and the word “a” or “an” doesn't exclude more than one. In addition, any reference numerals in the claims should not be interpreted as the limitation to the scope of the present disclosure.