DE102010049603A1 - Cable for use as wiring between chassis or vehicle frame and wheel of electric vehicle, has outer sheath and conductor strand comprising flexibilities coordinated together such that outer sheath is rigid than enclosed strand by tensile load - Google Patents

Abstract

The cable (1) has a conductor strand (6) enclosed by an outer sheath (5), which comprises a flexible wire mesh (7). The wire mesh is embedded into plastic or rubber. Resiliences of the outer sheath and the conductor strand are coordinated together in such a manner that the outer sheath is rigid than the enclosed conductor strand by tensile load. The conductor strand comprises corrugated characteristics within the outer sheath. An electrically conductive fabric made of fibers or the flexible wire mesh is formed in the outer sheath or outside the cable.

Description

The invention relates to a cable with at least one conductor strand, which is enveloped by an outer shell.

The invention further relates to a vehicle having such a cable as wiring of a wheel driven by a wheel hub motor.

In the near future, general mobility will undergo a major transformation. Electrically powered vehicles will become increasingly popular. One possible drive variant here is a wheel hub motor. The wheel hub motor is usually integrated directly into a wheel or a rim of a vehicle and performs a similar spring movement during driving as the wheel itself. The energy required for the drive is usually supplied via a wiring. Due to a relative movement between the wheel hub motor and the chassis or frame of the vehicle caused by the spring movement, special wiring is required to transmit the drive energy. Due to the relative movement between the wheel hub motor and the chassis, continuous stretching and bending movements occur, which in particular have an adverse effect on conductors and braids in the off-center region of the cable and can destroy them.

A designed as a hybrid cable is exemplified in the publication DE 10 2006 030 180 A1 previously known. In order to design such a hybrid cable for electric drives in such a way that the best possible shielding between power supply and signal line can be realized and that protection of the connected peripherals is ensured in the event of a short circuit, it is proposed that signal conductors and energy conductors designed as electrical conductors each have independent shieldings , In addition, the signal conductors should run centrally in the middle of the cable with the surrounding shielding, while the power conductors and any additional conductors are guided off-center in the cable sheath of the cable. However, such a hybrid cable does not solve the problem caused by relative movements between the wheel hub motor and the chassis of a vehicle and thereby continuous bending and stretching movements of the cable.

The invention has for its object to further develop a generic cable such that this is characterized by a secure and durable wiring even with continuous bending movements. The cable should in particular be integrated as a wiring between a chassis and a hub motor in existing chassis configurations of vehicles.

The solution according to the invention is characterized by the features of claims 1, 4, 9 and 10. Advantageous embodiments are described in the subclaims.

An inventive cable with at least one conductor strand, which is enveloped by an outer shell having a flexible wire mesh, which is embedded in a plastic or rubber, is characterized in that compliances of the outer shell and the conductor strand are coordinated so that the outer shell Under tensile load is stiffer than the coated conductor strand.

Under the tensile load is understood to mean a load which acts on the components within the cable, in particular in the axial or paraxial direction of the cable. Such a tensile load arises not only by a train in the longitudinal direction of the cable, but also when bending the cable. A stiffer outer shell is understood in particular to mean that the outer shell yields less than the conductor strand surrounded by it.

The solution according to the invention makes it possible to optimize a cable for wiring a wheel hub drive for electric vehicles, in particular the electric motor of electric vehicles. The cable thus has sufficient flexibility, in particular in a temperature range between -40 ° C and + 150 ° C.

In an advantageous embodiment according to a first variant and first embodiment, in the case of the cable, the sheathed conductor strand has a corrugated course within the outer sheath. In the case of a cable, this is made possible in particular by virtue of the fact that the sheathed conductor strand allows at least one change in length corresponding to an average change in length of a cable circumference of the cable in its longitudinal direction when the cable is bent. Equivalent to this is also a fabric or wire mesh to see, which is arranged as a screen in the outer shell of the cable or inside the outer shell of the cable adjacent.

In an advantageous embodiment according to a first variant and second embodiment of the cable in the outer shell or off-center of the cable and the outer shell adjacent an electrically conductive fabric made of fibers or an electrically conductive wire mesh is formed, wherein the fabric of fibers or the wire mesh unbalanced over a Cross-section of the cable is formed. Also off-center of the cable can be arranged another conductor strand, wherein cores of the further conductor strand are formed asymmetrically over a cross section of the cable. Due to the asymmetrical design of the fibers or conductors Depending on the configuration, a preferred radius for a bending of the cable is predetermined, in which the individual components of the cable are arranged in a preferably uniformly relaxed orientation.

In particular, such an asymmetrical design of fibers, conductors or the like can also be formed over a total length of the cable on a limited section of the cable. This is advantageous if, in the case of a supply of, for example, a wheel hub motor, only a limited cable section with a radius extending in a curved manner extends between a vehicle chassis and a wheel.

In an advantageous embodiment according to a first variant and third embodiment, one or preferably two or more stiff strands are used running in the cable in the outer shell extending in the longitudinal direction of the cable. These can be incorporated particularly advantageous right and left of the adjusting under bending neutral fiber as stiffening strands, so that the total strand of the cable receives a preferential bending direction and at the same time a higher shell stiffness under train.

According to a second variant of the cable according to the invention with at least one conductor strand, which is enveloped by an outer shell, the outer shell for mechanical protection of the conductor strand consists of individual segments. Such segments give a particularly good protection and a particularly high stability.

It is advantageous if in the cable, the segments engage in such a way that form joints between the individual segments and they form a tensile and flexible structure, with a neutral fiber is formed in the joints between the individual segments. Such joints may be formed in particular by structures in the manner of a pin or a pin receiving on the individual segments.

Alternatively, or combined with the cable, at least one stiffening strand may be integrated into the structure on at least one side of the segments in such a way that the at least one stiffening strand assumes hinge function and stiffening in one.

In this embodiment, it is preferred if in the cable two or more rigid cords are integrated as such stiffening strands on both sides of the segments in the structure so that they take over the hinge function and stiffening in one.

In an advantageous embodiment, the segments consist of curved stamped parts in the cable. The production as stamped parts not only allows the production of the rough contours of the segment at the same time but also an embodiment of other segment features such as a bend or a configuration of pins, pin receptacles or through holes for passing a rope or cable.

According to a third variant of the cable according to the invention with at least one conductor strand, which is enveloped by an outer shell, the outer shell for mechanical protection of the conductor strand on a single or multi-spiral enclosure.

An inventive use of such a cable takes place in particular in a vehicle, in particular electric vehicle, in which at least one cable designed in this way runs as wiring between a vehicle frame or chassis and a wheel driven by a wheel hub drive or other electric motor. Thus, a function-optimized design of a wiring for wheel hub drives of a wheel hub drive designed as an electric motor for electric vehicles is provided. In addition to drives as fully fledged vehicle drives such electric motors can also be used as support drives in addition to z. B. be configured as an internal combustion engine.

Common to all embodiments described is that the outer shell is under tensile load stiffer than the coated conductor strand. This can be achieved by different measures, which turn off the material or the structure of the outer shell itself or on the structure of the screen or even the structure of the conductor strand itself. One focus is on the design of the outer shell and the screen recorded therein, which is designed as a fabric, mesh or segments.

The cable according to the invention is due to the optimal flexibility to existing space conditions in a particularly advantageous manner in vehicles with a wheel hub motor integrated. There are no restrictions on the use of the cable. Thus, it can preferably be used to supply energy to a wheel hub motor.

A control of the motor and a transmission of sensor signals from the engine inside to control devices in the vehicle can also be done by optical fibers, with a insensitivity to electromagnetic interference pulses is advantageous. However, in addition to or alternatively to a power supply also electrical Signals are transmitted via signal lines located in the cable.

With the proposed solutions a sufficient shielding against glitches is guaranteed to meet requirements for electromagnetic compatibility. This shielding is intended to prevent the propagation of interference pulses to the outside, as well as a transmission of interference pulses in the engine. Furthermore, the individual versions offer the advantage in the event of an accident or mechanical damage by z. B. Marten bites to provide adequate protection. Since the loads in accidents can be so high that a separation of the wheel from the vehicle body is inevitable, a manageable separation of the wiring should be ensured. This can be done via a known special isolation clutch, which will not be discussed here. Important for the safe operation of this coupling, however, is a sufficient resistance of the wiring against demolition, so that the release force of the safety isolating coupling in any case should be well above the failure limit of the leads or cables.

There are no restrictions on the design of the cable. This can be formed as required from a variety of known materials and with one or more conductor strands.

The solution according to the invention is explained below with reference to a figure. It details the following:

1a illustrates in schematic simplified representation based on a partial sectional view of a section of a vehicle with a wheel and a cable designed according to the invention for wiring a wheel hub motor of the wheel;

1a schematically illustrates greatly simplified a detail B according to 1a ;

2a to 2c illustrate with reference to two longitudinal sections and a cross section of a second advantageous embodiment of such a cable according to the invention,

3a and 3b illustrate a third embodiment of a cable according to the invention executed;

4 clarified the structure of a shield of an alternatively configured cable according to the invention.

The 1a illustrates in schematic highly simplified representation of the basic structure and the basic function of a cable designed according to the invention 1 for wiring a motor, in particular wheel hub motor in the form of a Einzelradantriebes a wheel 3 in a vehicle. Only one wheel is shown 3 in a frontal view.

The wheel 3 is on a chassis or vehicle frame 2 of the vehicle by means of two double wishbones 4 attached or connected. The cable 1 is shown in a hanging loop shape. With solid lines, this arrangement is shown in a normal state. With dashed lines, the situation is shown in a sprung state, in which the wheel is raised relative to the chassis, thereby also the orientation of the double wishbones 4 and the course of the cable 1 change. In particular, a radius of the cable runs in a course offset from the previous position along the length of the cable 1 ,

1 Furthermore, a shows an enlarged detail A of the cable on the right center 1 in the relaxed state. The cable 1 consists essentially of an outer shell 5 , a ladder line 6 and a woven wire mesh of an electrically conductive material. The focus of the considerations below is in particular the outer shell 5 the harness, which in particular the requirements for bending and stretching movements of the cable 1 should meet.

To understand the stretching movements in bends is in a schematic section B in 1b an arrangement of fibers is shown. These fibers are merely illustrative of the stretching effects in the various areas of the bent wire harness. A middle fiber with a length L0 is called a neutral fiber NF. The upper fiber corresponds in the installed state of an upper or inner fiber IF. The inner fiber IF has a conductor length in the normal state or relaxed state which is shorter than the length L0 of the neutral fiber NF by a difference length dL. The length of the inner fiber is therefore L0 - dL. The lower or outer fiber AF in the installed state accordingly has a length which is longer than the length L0 of the neutral fiber NF by the difference in length dL, so that L0 + dL holds.

A first preferred embodiment is in 1a illustrated by the middle section A and a further section C shown below. The further section C shows the cable 1 in an axially tensioned state. An essential aspect for this embodiment is the course of the central central conductor strand 6 , The ladder strand 6 has a wavy course inside the outer shell 5 , In addition, the outer shell 5 and / or their Material designed so that this envelope stiffen faster than the core with the conductor strand 6 if the cable 1 is stretched in the axial direction.

In this variant, a screen with a flexible wire mesh 7 encased, which takes over both an electrical and a mechanical shielding and is embedded in a plastic or rubber. The wire mesh 7 is designed so that the wires, despite the required tight packing density, z. B. against marten bite, in a bend of the strand or cable 1 can move against each other and thus offer only low bending resistance.

The situation under bending is as follows: Inside the strand or cable 1 is the neutral fiber NF with the length L0. On the outside of the bend, the length of the outer fiber AF is now L0 + dL. On the inside of the bend, the length of the inner fiber IF is now L0 - dL. It follows that the wrapping and in particular the outer shell 5 should be able to take a length of L0 ± dL. Will be the leader 6 now assumed to be approximately in the neutral fiber NF, its length corresponds approximately to the length L0 of the neutral fiber NF. This in turn implies that with straight laid cable strands no effective strain relief over the jacket is possible.

Therefore, the jacket or the outer shell 5 and the conductor strand (s) 6 in their compliance so coordinated that the outer shell 5 or the jacket under tensile load is always stiffer than the sheathed conductor bundle of the conductor strand 6 , In order to achieve this in the cable structure described above, the three embodiments described below are proposed, which are separate or simultaneously in a cable according to the invention 1 Can find application:
According to the first embodiment, which in the enlarged sections A, C in 1 is shown, the conductor strands 6 or the individual wires of a conductor strand 6 in the cable interior of the cable 1 intertwined and / or laid in a wave pattern. Preferably, these conductor strands or cores are spaced apart by a flexible encapsulation such that they are flexible in all required directions and at the same time allow a change in length, which is the sum of the length L0 of the neutral fiber NF, the difference length dL and a safety length, ie L0 + dL + L corresponds to _safety that is higher than an elongation of the sheath. Ideally, the intertwining of the conductors or cores caused by the resulting inductance compensation of the resulting by the parallel conductor or wire capacitance.

Instead of or in addition to this embodiment with a wavy course of the conductor strand 6 may additionally or alternatively, the wire mesh 7 the shield in the material of the outer shell 5 be constructed so as to a corresponding change in length of the outer shell 5 when bending the cable 1 to enable.

The 2a to 2c illustrate a second embodiment in which the conductor strand 6 arranged centrally in the cable harness and by a conductor strand shell 8th is surrounded. The conductor strand cover 8th can also be out of the ladder 6 adjacent material of the outer shell 5 be educated. In the outer shell 5 is again a fabric or wire mesh 7 arranged as a screen.

In the 2a The section of the wiring harness is shown in a state as a straight stretched strand. 2 B represents the section of the cable harness in a bent state, wherein the illustrated bending direction inversely to the in 1b sketched bending direction is. 2c illustrates the cable in the bent state in cross section.

The essential feature of this embodiment is that a fiber flow in the jacket or in the outer shell 5 is placed asymmetrically in the stretched strand. A basic idea is that with a defined routing of the cable 1 always the same side outside or inside, that is, the inside as described above a change in length of L0 - dL and the outside undergoes a change in length of L0 + dL. Accordingly, the fibers or wires or the wire mesh 7 placed on the inside so that they are straight on cable 1 come in an extended position and run in a bent cable in particular crossed. On the outside is the fiber or are the wires or wires of the wire mesh 7 under bending of the cable in the extended position or in the extended position of the cable 1 crossed. It can be seen that the bent strand is the relaxed design state, while in the stretched state, the inner fiber takes over the strain relief for the core area.

According to the third embodiment, which also based on the 2a to 2c is represented, it is assumed that a uniform configuration of the fiber flow, in which the total strand of the cable 1 has no preferred direction for a bend and thereby, as mentioned above, has the disadvantage that the jacket or the outer shell 5 in stretched position under tension it always becomes longer than the neutral fiber.

This property can be remedied if a neutral fiber NF in the outer jacket or in the outer shell 5 is created. This is by means of in particular, two stiff strands can be implemented, which right and left of the adjusting under bending neutral fiber NF as stiffening strands 9 in the coat or the outer shell 5 be incorporated. The total strand of the cable 1 thus gets a preferential bending direction and at the same time a higher shell rigidity under tension.

Which of the embodiments described above individually or in combination with each other in a cable according to the application 1 depend on whether a preferred direction under bending exists or whether the total strand should be bendable in different directions.

In particular, the second embodiment with the over the cross section of the cable 5 different and asymmetrical course of the fibers can also be over a total length of such a cable 1 considered only in a section of the cable 1 be educated. When used in a vehicle according to 1 so preferably only that portion of the cable 1 Such asymmetrical course, which is subject to a corresponding bending direction in the installed state.

Elements for the configuration of a second variant are based on 3a and 3b shown. In principle, however, a combination with features of the other variants can be implemented. 3 shows on the left two exemplary umbrella segments 10 , which are shown in the disconnected state. 3a illustrates the composite state of the umbrella segments 10 , The screen accordingly consists of individual such screen segments 10 , which interlock in such a way that they form a tensile and flexible structure. Preferably, the umbrella segments 10 be formed as bent stamped parts.

According to a first embodiment, the individual umbrella segments 10 projections 11 in the form of particular cones and shots 12 in the form of particular pin shots on. Such pins and pin receptacles can in particular in one embodiment as a bent stamped part in the manufacture of the individual umbrella segments 10 be molded into this. Preferably, in the assembled state, the neutral fiber is located in the region of the joints between the individual of the umbrella segments 10 , The joints are preferably formed by the meshing pin and pin receptacles. Under train becomes such a screen 7 * take a length corresponding to the neutral fiber plus the elastic or overload plastic deformation of the overall structure.

Such a segment screen from the umbrella segments 10 behaves as a screen 7 * stiffer under tension than the fabric screen, which in the first variant according to the 1a to 2c is described. However, the screen shows 7 * according to this second variant against the fabric or wire mesh 7 from the first variant with parallel aligned joints between the individual umbrella segments 10 a unique preferred direction of travel, which should be strictly observed when using the wiring.

According to a second embodiment of this second variant, as an alternative to the joints formed by the pins and pin holders, two stiff cords can be attached to both sides of the umbrella segments 10 be integrated into the structure so that they take on a hinge function and stiffening in one. Instead of cords, cables or other suitable structures can be used. In this case, the shield segments now serve the mechanical protection of the internally arranged wires.

The two embodiments of this second variant can be seen in analogy to structures known per se. Thus, the principle of action of the first embodiment of the second variant is comparable to a human spine, in which articulated envelope body the sensitive lines or conductor strands 6 protect inside. The second embodiment of the second variant is similar to the action principle of a chute in the construction industry, in which rigid conical tubes are hung on two chains together and so form a flexible but durable tube.

4 represents a third variant, which is constructed analogously to a shower hose. Individual such alternative umbrella segments 13 consist of a preferably bent stamped part, which is bent almost cylindrically in cross section. At the same time, such a spiral casing serves as strain relief and as crush protection for the conductor strand arranged in the center, wherein the bending radius is limited. Instead of the illustrated individual segments but also one or more spiral configurations of umbrella segments can be used. In principle, however, a combination with features of the other variants can be implemented.

The solution according to the invention is not limited to the embodiment shown in the figures. Modifications are possible. It is crucial that with this configuration a permanently secure cabling despite a high load of the cable 1 by continuous deflections of the wheel relative to the chassis of the vehicle and the resulting continuous stretching and bending movements of the cable 1 is possible.

LIST OF REFERENCE NUMBERS

1

electric wire

2

vehicle frame

3

wheel

4

Double wishbone

5

outer shell

6

conductor lane

7, 7 *, 7 °

Wire mesh or screen

8th

Conductor strand shell

9

stiffening strip

10

screen segment

11

Projection, in particular cones

12

Recording, in particular pin recording

13

alternative screen segment

AF

outer fiber

± dL

Difference length of length compared to neutral fiber

IF

inner fiber

L0

Conductor length of neutral fiber

NF

neutral fiber

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102006030180 A1 [0004]

Claims (10)

Electric wire ( 1 ) with at least one conductor strand ( 6 ), of an outer shell ( 5 ), which is a flexible wire mesh ( 7 ) which is embedded in a plastic or rubber, characterized in that compliances of the outer shell ( 5 ) and the conductor strand ( 6 ) are coordinated so that the outer shell ( 5 ) under tensile load is always stiffer than the coated conductor strand ( 6 ). Electric wire ( 1 ) according to claim 1, characterized in that the coated conductor strand ( 6 ) within the outer shell ( 5 ) has a wavy course. Electric wire ( 1 ) according to claim 1 or 2, characterized in that in the outer shell ( 5 ) or off-center of the cable ( 1 ) and the outer shell ( 5 ) adjacent an electrically conductive fabric made of fibers or electrically conductive wire mesh ( 7 ) or that off-center of the cable ( 1 ) a further conductor strand is arranged, wherein the fabric of fibers or the wire mesh ( 7 ) asymmetrically over a cross-section of the cable ( 1 ) is formed or wires of the further conductor strand asymmetrically over a cross section of the cable ( 1 ) are formed. Electric wire ( 1 ), in particular according to one of claims 1 to 3, with at least one conductor strand ( 6 ), of an outer shell ( 5 ) is enveloped, characterized in that the outer shell ( 5 ) for mechanical protection of the conductor strand consists of individual segments. Electric wire ( 1 ) according to claim 4, characterized in that the segments ( 10 ; 13 ) in such a way that joints between the individual segments ( 10 ; 13 ) and they form a tensile and flexible structure, with a neutral fiber in the region of the joints between the individual segments ( 10 ; 13 ) is formed. Electric wire ( 1 ) according to claim 4 or 5, characterized in that at least one stiffening strand ( 9 ) on at least one side of the segments ( 10 ; 13 ) is integrated into the structure such that the at least one stiffening strand ( 9 ) Hinge function and stiffening in one takes over. Electric wire ( 1 ) according to claim 6, characterized in that two or more rigid cords are used as such stiffening strands ( 9 ) on both sides of the segments ( 10 ; 13 ) are integrated into the structure so that they take on hinge function and stiffening in one. Electric wire ( 1 ) according to one of claims 4 to 7, characterized in that the segments ( 10 ; 13 ) consist of bent stamped parts. Electric wire ( 1 ), in particular according to one of claims 1 to 8, with at least one conductor strand ( 6 ), of an outer shell ( 5 ) is enveloped, characterized in that the outer shell ( 5 ) For mechanical protection of the conductor strand has a single or multi-spiral enclosure. Vehicle, in particular an electric vehicle, in which at least one cable is used as a wiring between a chassis or vehicle frame ( 2 ) and a wheel driven by a wheel hub drive or other electric motor ( 3 ), characterized in that the cable ( 1 ) is designed according to one of claims 1 to 9.

Images