Vehicle charging cable

Abstract

The present invention relates to a cable, such as a vehicle charging cable for transmitting electric power between an electric current source and an electric current load, such as the battery of a vehicle, the cable comprising: - an elongate cable body, extending substantially along a longitudinal cable direction, having a width in a first, e.g. transverse, direction perpendicular to the longitudinal cable direction and having a height in a second, e.g. vertical, direction perpendicular to the longitudinal cable direction and the first direction, and - a plurality of conductors inside the cable body, extending along the longitudinal cable direction. The cable body has a non-circular cross-section, in a plane perpendicular to the longitudinal cable direction, and the height of the cable body is smaller than the width of the cable body.

Description

[0001] Title: Vehicle charging cable

[0002] Field of the invention

[0003] The present invention relates to a cable, such as a vehicle charging cable for transmitting electric power between an electric current source and a vehicle. The present invention further relates to a method of transmitting electric power between an electric current source and an electric current load, such as the battery of a vehicle.

[0004] State of the art

[0005] At present, several types of vehicle charging systems are known to provide electric power to a vehicle, such as an electric or plug-in hybrid car, truck, motorcycle or the like. In practice, most systems have charging cables to establish an electric connection between an electric current source, such the electricity grid, and the vehicle, e.g. the battery thereof.

[0006] A first example of such a charging cable is disclosed in European patent application EP 3 707 091 A1, which discloses a portable reel onto which a vehicle charging cable can be wound. This known reel may offer convenient storage of the cable when it is not used for charging the vehicle.

[0007] However, this cable has the drawback that it may form an obstruction for passers-by. If, for example, the cable is laid over a sidewalk or the like, extending between a private charging socket mounted at a wall of a building and a vehicle parked on the street, it may cause tripping of persons walking over the sidewalk. It may also form an obstruction for wheelchairs or walkers, that may have difficulties in being rolled over the wire.

[0008] A solution was proposed in WO 2021 / 239884 A1, which discloses a cable that is wound on an overhead stationary reel, so that the cable may only need to be lowered to the charging port of the vehicle. This overhead reel does not need to have any cable laying on the ground, such as over the sidewalk, so that the risk of tripping is reduced significantly.

[0009] However, this overhead reel system is relatively complex, which means that it is expensive to install, especially for private users. Furthermore, the overhead reel system is stationary, which means that each charging location needs to be provided with such an overhead reel or that a separate cable still needs to be used at a charging location where no overhead reel system is present.

[0010] GB 2596925 A discloses a charge mat for electric vehicles in which a cable is integrated. This known charge mat has large dimensions, measuring at least 800 mm in length and 300 mm in width, and includes a conductor for guiding electric currents towards a vehicle. Object of the invention

[0011] It is therefore an object of the invention to provide a vehicle charging system, e.g. a vehicle charging cable, that lacks one or more of the above drawbacks, or at least to provide an alternative vehicle charging system.

[0012] Detailed description

[0013] The present invention provides a cable, such as a vehicle charging cable for transmitting electric power between an electric current source and an electric current load, such as the battery of a vehicle, the cable comprising: an elongate cable body, extending substantially between two ends of the cable in a longitudinal cable direction, having a width in a first, e.g. transverse, direction perpendicular to the longitudinal cable direction and having a height in a second, e.g. vertical, direction perpendicular to the longitudinal cable direction and the first direction, and a plurality of conductors inside the cable body, extending between the ends of the cable in the longitudinal cable direction, wherein the cable body has a non-circular cross-section, in a plane perpendicular to the longitudinal cable direction, and wherein the height of the cable body is smaller than the width of the cable body.

[0014] The cable according to the present invention has a cable body that is configured to form a shielding for the conductors inside it. The cable body may be flexible, to be bent, and may be made of an electrically insulating material. The cable may further be configured to be wound on a reel.

[0015] The cable body is elongate, parallel to the length of the cable and along the longitudinal cable direction. The conductors in the cable body extend over the length of the cable, to electrically connect a first end of the cable with a second end of the cable, opposite to the first end.

[0016] The cable may for example have a length along the longitudinal cable direction in the range between 3 meter and 10 meter, for example about 5 meter or 7 meter, but other lengths can be envisaged as well.

[0017] It is noted that the longitudinal cable direction may, but not necessarily needs to, be a straight line along the cable. However, the cable may be curved as well, for example at a transition from the ground towards a charging port of a vehicle or towards a distribution unit that is elevated from the ground. With a curved cable, the longitudinal cable direction at any point along its length may be defined as the direction perpendicular to the cross-section of the cable at that point. The length and the width of the cable body may be defined in a cross-sectional plane of the cable, perpendicular to the longitudinal cable direction. The width of the cable body is defined in a first direction, for example referred to as a transverse direction, which may be aligned horizontally when the cable is disposed on the ground during use of the cable. Similarly, the height of the cable is defined perpendicular to the width, for example aligned vertically with the cable laying on the ground.

[0018] According to the present invention, and opposed to existing cables, the present cable does not have a circular cross-section. As such, the present cable may not roll over the ground, in particular upon interaction with the feet of passers-by or the wheels of a wheelchair or a walker.

[0019] Furthermore, the present cable is relatively wide, compared to its height, which implies that the cable is relatively stable when it lays on the ground. This may prevent sliding or shifting of the cable, and may prevent that the cable will tilt or rotate when it inadvertently interacts with feet or wheels.

[0020] Furthermore, the relatively low height of the cable may provide that a passer-by will step on it, instead of bumping against it. Hence, the ground itself, in particular a sidewalk made of tiles, may have an uneven surface by itself, for example being caused by a difference in height between adjacent tiles.

[0021] Preferably, the height of the cable is less than the height difference between tiles, so that a passer-by, who already adapts its step to accommodate for the height differences between tiles, will not need to do any further effort to adapt its step for accommodating to the height of the cable.

[0022] In an embodiment, the conductors of the cable are arranged in the cable body side-by- side, parallel to the first, e.g. transverse direction. This may provide that, opposed to existing cables in which the conductors were disposed around a central axis, the cable can be provided relatively flat, since the cable only needs to have a height corresponding to a single conductor.

[0023] In a further embodiment, the height of the cable body is at least five times smaller than the width of the cable body, preferably at least ten times smaller than the width of the cable body. It was found by the present inventor that a ratio between cable height and width in this range may be beneficial in reducing the risk of tripping over the cable.

[0024] In a further or alternative embodiment, the height of the cable body is smaller than 20 mm, preferably smaller than 10 mm, for example about 5 mm. It was found by the present inventor that with a height being smaller than 20 mm, especially if the height is less than 5 mm, the risk of tripping over the cable is reduced.

[0025] Especially, local laws of municipalities may limit a maximum allowable height difference between tiles in a sidewalk to be 5 mm. If the height of the cable is about 5 mm, the difference in height imposed by the cable itself will not be any worse than height differences of the sidewalk itself, so that the use of the cable, whilst laying on the sidewalk, may not impose any danger.

[0026] In an embodiment, the width of the cable body is smaller than 150 mm, preferably smaller than 100 mm, for example about 70 mm. It was found by the present inventor that with a width being smaller than 150 mm, especially if the width is less than 70 mm, the risk of tripping over the cable can be reduced as well.

[0027] In an embodiment, the cable body has a substantially rectangular cross-section. This rectangular cross-section may improve the stability of the cable, whilst laying on the ground, to further reduce the risk of tripping over the cable or for bumping against the cable.

[0028] In an alternative embodiment, the cable body has a substantially trapezoid crosssection. Seen along the longitudinal cable direction onto the trapezoid cross-section, the cable may rest on the ground with the wide horizontal edge of the trapezoid, whereas the narrow edge may form an upper edge of the cable body.

[0029] The side surfaces of the trapezoid-shaped cable body may extend diagonally upward, from the lower, wide edge towards the upper, narrow edge. The side surfaces may form a ramp, so that a wheel can roll over the cable more easily, compared to when the side surfaces are aligned vertically, as with a cable body having a rectangular cross-section. This trapezoid shaped cable body may offer a further reduction of the risk of tripping over the cable.

[0030] In an embodiment, the cable body has a bottom surface, configured to be arranged on a ground, e.g. a sidewalk, at least partially during use of the cable for transmitting electric power, and the cable body has a top surface, opposite to the bottom surface, which is configured to face upwards during use.

[0031] During use, the cable is intended to lay on the ground with its bottom surface and the top surface faces upwards. After use, the cable can be wound on a reel, so that the bottom surface comes to lay on the top surface of a previous winding of the cable. In a further embodiment, the top surface has a curved shape, curving downwards towards the opposed sides of the cable body. The curved top surface may provide a smooth profile, so that the risk of tripping is reduced any further. Furthermore, the smooth top surface may be beneficial for wheelchairs or walkers, since the cable may not have an abrupt change in height, but rather gradual instead.

[0032] At the sides of the cable body, seen in the first, e.g. transverse direction, the cable body is relatively low, having a low height. This allows the top surface of the cable body to be located near the surface of the ground adjacent the cable, so that the difference in height between them is minimized. At the centre, in between the sides of the cable, the cable body may have a larger height, for example to accommodate the conductors inside the cable body.

[0033] In an alternative embodiment, the top surface has a flat central portion and side ramp portions at opposed sides of the flat central portion, which slope downwards towards the opposed sides of the cable body. According to this embodiment, the cable body comprises a ramp portion at both sides, seen in the first, e.g. transverse direction, so that the cable body is relatively low at its sides, to reduce the risk of tripping and to facilitate passage of wheelchairs or walkers over it. In between the side ramp portions, the flat central portion may be relatively high, so that it offers room for the accommodation of the conductors. The cable body may have a smooth transition between the side ramp portions and the central portion.

[0034] Optionally, the width of the flat central portion in the first, e.g. transverse direction may be relatively large, compared to the width of the side ramp portions.

[0035] Alternatively, the width of the flat central portion may be relatively small, so that the majority of the top surface is formed by the side ramp portions. This may be beneficial where a sloping angle of the side ramp portions, relative to the ground, is small.

[0036] In a further embodiment, the side ramp portions have an inclination of less than 45°, preferably less than 30°, for example about 20°. These inclinations may be defined as an angle between the side ramp portions of the top surface and the bottom surface, i.e. between the side ramp portions and the ground.

[0037] It was found by the present inventor that an inclination in this range may allow for improved passage of wheelchairs or walkers, whilst still offering sufficient room to minimize material usage for the cable body and to allow for sufficient room to accommodate the conductors.

[0038] In an embodiment, one or both of the side ramp portions may have planar contour, i.e. being aligned at a constant inclination angle. Alternatively or additionally, one or both of the side ramp portions may have a curved contour. The top surface may be either curved upwards or downwards at the side ramp portions, for example to form a gradual transition between the ground, i.e. the sidewalk, and the side ramp portions and / or between the side ramp portions and the flat central portion.

[0039] In an alternative embodiment, the top surface may be solely formed by ramp portions at opposed sides of the cable body, which slope downwards towards the opposed sides of the cable body. According to this embodiment, the cable body is formed by two ramp portions that are sloping and that also accommodate of the conductors. This cable body may have a smooth transition between both ramp portions, to improve the passage of wheelchairs or walkers.

[0040] In an embodiment, the top surface of the cable body is an anti-slip top surface, for example comprising a plurality of grooves and ridges extending in the longitudinal cable direction or extending in a direction having at least a component parallel to the longitudinal cable direction, for example extending at a 45-degree angle relative to the longitudinal cable direction.

[0041] The anti-slip surface may contribute to the safety of the cable, since it may reduce the risk of slipping when a passer-by would step on the cable with its foot. Especially in wet conditions, other cables may cause slipping, but the present embodiment may allow for a safer cable.

[0042] It may be particularly beneficial to have grooves extending in directions having at least a component parallel to the longitudinal cable direction, since the persons walking over the sidewalk typically walk in a direction perpendicular to the longitudinal cable direction. This means that the additional friction or anti-slip effect of the grooves is most beneficial when the grooves extend in directions perpendicular to the walking direction and parallel to the longitudinal cable direction.

[0043] The anti-slip surface may be formed by a geometrical structure on the top surface, such as a pattern of local elevations and depressions. As an example, the top surface may comprise a grid-like pattern of upwards protrusions, surrounded by a lower, nominal surface. Alternatively, the geometrical structure may be formed by upwardly protruding ridges, which are neighboured by grooves that are placed lower, compared to the ridges.

[0044] In an embodiment, the top surface of the cable body comprises a central valley extending over the length of the cable body in the longitudinal cable direction. The central valley may have an ellipsoid shape, seen in a cross-sectional plane perpendicular to the longitudinal cable direction, so that side parts of the top surface are somewhat higher than a middle part in between the side parts.

[0045] In an embodiment, the cable body comprises at least one central cavity, extending through the cable body between the ends of the cable in the longitudinal cable direction, wherein the conductors extend through the at least one central cavity, and wherein the cable body comprises at least one short-circuit shielding in the at least one central cavity that surrounds one or more of the conductors, which shielding is configured to be connected to an electrical earthing during use.

[0046] The central cavity may extend over substantially the entire length of the cable, e.g. between the cable ends in the longitudinal cable direction. Seen in a cross-sectional plane perpendicular to the longitudinal cable direction, the cavity may be provided in the centre of the cable body, so that the cavity is inaccessible from the outside and shielded against external influences.

[0047] The conductors extend in the cavity, so that they are shielded from the outside as well. The short-circuit shielding is arranged to surround the conductors, so that, in the event of inadvertent damaging of the cable body, a physical barrier may be formed around the conductors. To this effect, the short-circuit shielding may be embodied as a wire mesh around the conductors or as an aluminium tape wound around the conductors.

[0048] The short-circuit shielding may be electrically conductive and may furthermore be connectable to an electrical earthing during use, so that a ground fault circuit interrupter may be activated in case one or more of the conductors ends up in electrical contact with the short-circuit shielding upon damaging of the cable.

[0049] The central cavity, in cross-section, may be shaped similar to the overall shape of the cable body. With the cable body being relatively wide, having a large width relative to its height, the central cavity may be relatively wide in the first, e.g. transverse direction as well.

[0050] In a further embodiment, the cable body comprises a single cavity, e.g. being elongate in the first direction, in which all conductors are arranged side by side, wherein the cable body comprises a single common short-circuit shielding in the cavity that surrounds all conductors.

[0051] The cable according to this embodiment has a single cavity for all of the conductors. All conductors thereby share a single short-circuit shielding, which may follow the profile of the cavity, in which all conductors are arranged.

[0052] The cavity may be elongate in the first, e.g. transverse direction, to allow all conductors to be arranged side-by-side in the first direction. As such, only a single vertical layer of conductors may be presents inside the cavity, to minimize the height of the cable. In an alternative embodiment, the cable body comprises a plurality of cavities, corresponding to the number of conductors, in each of which a single conductor is arranged, wherein the cable body comprises a plurality of short-circuit shieldings, corresponding to the number of conductors, each arranged in a different cavity to each surround a single conductor.

[0053] According to this embodiment, the conductors each have their own cavity and their own short-circuit shielding. In particular, the conductors may be formed by multiple cores, which may each be arranged in a distinct cavity with their own shielding.

[0054] The conductors, e.g. the cores, in the cable according to the present embodiment are shielded from each other by the cable body, as a result of the separate cavities. This may reduce the risk of short-circuiting inside the cable, to improve the safety of the cable.

[0055] The cavities may all be arranged side-by-side in the first direction. As such, only a single vertical layer of cavities may be presents inside the cavity, having a single layer of conductors, to minimize the height of the cable.

[0056] In an embodiment, each of the conductors is formed by a plurality of electrically conductive cores that are electrically insulated from each other over the length of the cable along the longitudinal cable direction and that are connected to each other at the ends of the cable body. This may provide the benefit that the overall cross-sectional area of each conductor, e.g. the combined cross-sectional area of all cores, can be increased without having to increase the diameter of individual cores.

[0057] In case it is desired to increase a maximum electric current that can be conducted safely, a skilled person would normally increase the diameter of the conductors. This may result in a drawback, since an increased diameter of the conductors would result in an unfavourable increase in height of the cable, which is undesired as it could become a larger obstruction.

[0058] Instead, the present embodiment achieves that the cross-sectional area of the conductors is increased by increasing the number of cores, without requiring diameters of conductors, i.e. cores, to be increased. The cores of each of the conductors are insulated from each other, for example being arranged in separate cavities of the cable body, and are solely connected to each other at the ends of the cable body, so that electric currents in each of the conductors are spread over the cores.

[0059] In a further embodiment, the cable is three-phase cable, in particular a three-phase vehicle charging cable, comprising five conductors, wherein a first conductor is formed by a first and a second core, configured to transmit a first phase, a second conductor is formed by a third and a fourth core, configured to transmit a second phase, a third conductor is formed by a fifth and a sixth core, configured to transmit a third phase, a fourth conductor is formed by a seventh and an eighth core, connectable to a neutral phase, and a fifth conductor is formed by a ninth and a tenth core, connectable to the electrical earthing.

[0060] The cable according to this embodiment may be able to facilitate three-phase charging of vehicles, as it has three conductors to transmit alternating-current electric power, for example having a phase shift of 120° between the phases. A further conductor, the fourth conductor, is provided to become a neutral phase during charging of a vehicle and a fifth conductor is configured to be connected to an earthing, for example being connected to the short-circuit shielding of the cable.

[0061] According to the present embodiment, the cable comprises two cores for each of the conductors, so at least ten cores in total. Preferably, all cores are arranged side-by-side in the first, e.g. transverse direction, to minimize the height of the cable. Optionally, one or more of the conductors may comprise more than two cores per conductor, i.e. to further increase a maximum allowable current that can be transmitted.

[0062] In addition, the vehicle charging cable may comprise two further conductors, which may be configured to transmit data signals between the electric current source and the vehicle. The further conductors may for example comprise a proximity pilot (PP) line, configured to establish pre-insertion signalling through the cable, for example to detect if a vehicle connector of the cable is connected properly to the vehicle charging port. The further conductors may also comprise a control pilot (CP) line, configured to establish post-insertion signalling through the cable, for example to monitor electric currents that are transmitted through the cable, i.e. supplied to the vehicle.

[0063] In an embodiment, the cable further comprises a first end section, connected to the cable body at a first end thereof, and a second end section, connected to the cable body at a second end thereof, wherein the first end section and the second end section have a crosssection different from the cable body, for example having a circular cross-section.

[0064] The cable according to this embodiment is composed of two end sections and the cable in between the end sections. The end sections have cross-sections that are different from the cross-section of the cable body in between them. Hence, the cable body has the flattened cross-section and the end sections have a circular cross-section.

[0065] The end sections with circular cross-section offer the benefit that they are more flexible and more bendable than the flattened cable body. This makes the end sections beneficial for use at the ends of the cables, which ends are not intended to lay on the street or on the sidewalk. The ends portions, instead, might need to be bent to extend towards the vehicle’s charging port and towards an electric current source. The first end section may extend between a wall outlet and the first end of the cable body. For example, this first end section may be disposed in the user’s front garden, extending downward from the wall outlet and towards the sidewalk. The flattened cable body can then be disposed on the sidewalk. Finally, the second end section may extend between the second end of the cable body and the vehicle’s charging port, for example extending upwards from the sidewalk towards the charging port.

[0066] In an embodiment, the length of the first end section may be in the range between 0,5 m and 5 m, preferably in between 1 m and 4 m, for example about 3 m. Similarly, the length of the second end section may be in the range between 0,5 m and 5 m, preferably in between 1 m and 4 m, for example about 3 m as well. Finally, the length of the cable body may be in the range between 2 m and 6 m, for example about 4 m.

[0067] In an embodiment, the width of the flattened cable body is smaller than 150 mm, preferably smaller than 100 mm, for example about 70 mm, with the height of the flattened being smaller than 20 mm, preferably smaller than 10 mm, for example about 5 mm.

[0068] Furthermore, according to this embodiment, the diameter of the first end section and / or the second end section may be smaller than 20 mm, preferably smaller than 15 mm, for example about 12 mm.

[0069] In an embodiment, the cable further comprises a first adapter element, arranged in between the first end section and the cable body, and a second adapter element, arranged in between the second end section and the cable body. The adapter elements serve as a transition between the respective end sections and the cable, in order to provide a smooth transition between their different cross-sections and to provide for improved shielding of the conductors extending between the respective end portions and the cable body.

[0070] The adapter elements may be moulded around the ends of the end portions and the cable body, for example by means of an injection moulding process. The moulding may provide the benefit that a unitary adapter element can be provided, which accurately seals around the ends of the end portions and the cable body and which may be free of seams, in order to prevent water or dirt from entering the adapter elements.

[0071] In a further embodiment, one or both of the adapter elements may be two-piece adapter elements. Each of the adapter elements thereby comprises a first adapter part, connected to the cable’s end section, and a second adapter part, connected to the cable body. For example, the first adapter part is moulded to the end section and the second adapter part is moulded to the cable body in a manner described above. The first adapter part is connectable to the second adapter part to establish an electrical connection between the cable body and the respective end section. For example, the first adapter part is insertable in the second adapter parts, or vice versa, to obtain a substantially watertight connection between the adapter parts, to prevent water or dirt from entering the adapter elements.

[0072] The separate adapter parts may offer the benefit that the cable can be built in a modular manner, for example allowing combination of several different first end sections, different cable bodies and different second end sections. A cable may thereby be made closely to a user’s requirement out of standard components.

[0073] For example, a user may have a front garden of about 2 meters, a sidewalk of about 2 meters in front of its house and a final length towards the charging port of his vehicle of about 3 meters. Accordingly, the cable for that user can be built with a first end section with a length of about 2 meters, a cable body with a length of about 2 meters and a second end section with a length of about 3 meters.

[0074] Should the user move towards another house with a 5 meter wide sidewalk, it may only require exchange of the cable body towards one with a length of 5 meters, whereas the first end section and the second end section may be kept.

[0075] In an additional or alternative embodiment, the conductors also extend through the first end section and the second end section, and, for at least one of the conductors, the number of cores per conductor in the cable body differs from the number of cores per conductor in the first end section and / or the second end section.

[0076] According to this embodiment, the number of cores per conductor in the cable body, with the small height of preferably less than 5 mm, may be larger than the number of cores per conductor in the end sections. Hence, the end sections may not be subject to narrow height dimensions, allowing the end sections to be provided as conventional cables, whilst still allowing conductors thick enough to be able to transmitted the electric current required for these purposes.

[0077] In an embodiment, each of the conductors consists of a single core in the first end section and / or the second end section. This may further offer the benefit that the end sections can be relatively bendable relative to the cable body, as a result of the lower number of cores.

[0078] In an embodiment, the conductors in the cable body are electrically connected to the conductors in the end sections in the respective adapter elements. In these adapter elements, the multiple cores of each conductor in the cable body are connected or connectable to the fewer, e.g. single core of that conductor in the end section. In this embodiment, the adapter elements further serve the purpose of shielding the electric connection between the different cores of each conductor against external influences.

[0079] In an embodiment of the vehicle charging cable, the cable has at least one type 2 connector attached to it, for example comprising a type 2 connector at each end. Such a type 2 connector may also be referred to as a “Mennekes connector”, being named after the company that originated the design of these connectors.

[0080] Alternatively, however, the cable may be provided with other connectors, such as a J plug connector or a CCS connector.

[0081] If present, the connectors are preferably attached to the respective end sections of the cable, i.e. to their ends opposite to the cable body. As such, seen along the longitudinal cable direction, the cable first comprises a first one of the connectors attached to the first end section, then the elongate body, followed by the second end section and, finally, a second one of the connectors.

[0082] In an embodiment, the cable body is made from an elastomeric material, for example comprising a polyurethane (Pll) material or ethylene propylene diene monomer (EPDM) rubber. Such an elastomeric material, especially the Pll and EPDM material, may offer sufficient strength and durability for the cable body, whilst still allowing for sufficient elasticity, for example to allow winding of the cable on a reel. Furthermore, this material may offer sufficient electric insulation, to shield the conductors from the outside and to provide insulation between the conductors themselves.

[0083] The present invention further provides a method of transmitting electric power between an electric current source and an electric current load, such as the battery of a vehicle by means of a cable as disclosed herein, in particular as recited in the appended claims, comprising the steps of: electrically connecting the cable to the electric current source with a first end, electrically connecting the cable to the electric current load, e.g. the vehicle with a second end, and establishing an electric current between the electric current source and the electric current load, e.g. the vehicle.

[0084] The method according to the present invention may comprise one or more of the features and / or benefits disclosed herein in relation to the cable, in particular as recited in the appended claims.

[0085] The method according to the present invention may offer transmission of electric energy between an electric current source and an electric current load, in particular offering charging and / or discharging of a battery of a vehicle, whilst forming a reduced hinder for passers-by that need to cross the cable, for example in case the cable extends over a sidewalk or the like. Alternatively, the cable may for example be used to transmit electric energy towards a distribution unit that is elevated from the ground, for example on a market place, on a building site or in a workshop.

[0086] The cable used in the method according to the present invention, and opposed to existing cables, does not have a circular cross-section. As such, the present cable may not roll over the ground, in particular upon interaction with the feet of passers-by or the wheels of a wheelchair or a walker. Furthermore, the cable is relatively wide, compared to its height, which implies that the cable is relatively stable when it lays on the ground. This may prevent sliding or shifting of the cable, and may prevent that the cable will tilt or rotate when it inadvertently interacts with feet or wheels. Furthermore, the relatively low height of the cable may provide that a passer-by will step on it, instead of bumping against it. Hence, the ground itself, in particular a sidewalk made of tiles, may have an uneven surface by itself, for example being caused by a difference in height between adjacent tiles.

[0087] The method may, but not necessarily needs to, comprise the step of unwinding the cable from a reel. The reel may be used for storage of the cable when it is not used for transmitting electric currents.

[0088] Furthermore, the method may comprise the steps of disconnecting the cable from the electric current load, e.g. the vehicle and the electric current source after charging is completed. Optionally, the method may comprise the step of winding the cable on the reel, after disconnecting the cable.

[0089] Brief description of drawings

[0090] Further characteristics of the invention will be explained below, with reference to embodiments, which are displayed in the appended drawings, in which:

[0091] Figure 1 schematically depicts an embodiment of the vehicle charging cable according to the present invention,

[0092] Figures 2a and 2b depict a cut open view and a cross-sectional view on an embodiment of a cable according to the present invention,

[0093] Figures 3a and 3b depict a cut open view and a cross-sectional view on another embodiment of a cable according to the present invention, and

[0094] Figure 4 schematically depicts an alternative embodiment of the vehicle charging cable according to the present invention. Throughout the figures, the same reference numerals are used to refer to corresponding components or to components that have a corresponding function.

[0095] Detailed description of embodiments

[0096] Figure 1 schematically depicts an embodiment of a vehicle charging cable, to which is referred with reference numeral 1. The cable 1 is configured to transmit electric power between an electric current source, in particular a wall-mounted electric vehicle (EV) charging box 100 and an electric current load, in particular a battery of an electric vehicle 101.

[0097] The cable 1 comprises an elongate cable body 10, which extends in a longitudinal cable direction L between two ends. At a first end, the cable 1 comprises a first type 2 connector A. The cable 1 further comprises a second type 2 connector (B) at a second end, opposite to the first end, seen along the longitudinal cable direction L

[0098] The present cable body 10 is made of ethylene propylene diene monomer (EPDM) rubber, which is an elastomeric material. Alternatively, the cable body can, for example, comprise polyurethane (Pll) material.

[0099] The cable body 10 has a bottom surface 11, which is laid on a sidewalk 150 in the representation in figure 1, and has a top surface 12, opposite to the bottom surface 11, which faces upwards.

[0100] The cable 1 comprises a plurality of conductors 20 inside the cable body 10, which extend between the ends of the cable 1 in the longitudinal cable direction L. The conductors 20 are connected to the connectors A, B at the ends of the cable 1, in order to transmit electric energy between the connectors A, B, via the conductors 20. The cable body 10 is thereby configured to form a shielding for the conductors 20 inside it and is flexible, to be bent and to be wound on a reel.

[0101] It is best shown in figures 2b and 3b, which are cross-sectional views on the cables 1 in a plane perpendicular to the longitudinal cable direction L, that the cable body 10 has a width W in a transverse direction, perpendicular to the longitudinal cable direction L, and that the cable body 10 has a height H in a vertical direction perpendicular to the longitudinal cable direction L and the transverse direction.

[0102] According to the present invention, the cable body 10 has a non-circular cross-section in the plane displayed in figures 2b an 3b. In particular, the cable body 10 according to the present embodiment has a substantially trapezoid cross-section. The trapezoid-shaped cable body 10 comprises side surfaces that extend diagonally upward, from the bottom surface 11 to the top surface 12. The side surfaces form a ramp, so that a wheel can roll over the cable 1 more easily and that a risk of tripping over the cable 1 is reduced.

[0103] Furthermore, the height H of the cable body 10 is smaller than the width W of the cable body 10. In the present embodiment, the height H of the cable body 10 is at least ten times smaller than the width W of the cable body 10. In particular, according to the present embodiment, the height H of the cable body 10 is about 5 mm and the width W of the cable body 10 is about 75 mm.

[0104] The top surface 12 of the cable body 10 has a flat central portion 13 and side ramp portions 14, 15 at opposed sides of the flat central portion 13, which slope downwards towards the opposed sides of the cable body 10. As a result, the cable body 10 is relatively low at its sides, to reduce the risk of tripping and to facilitate passage of wheelchairs or walkers over it.

[0105] In between the side ramp portions 14, 15, the flat central portion 13 is relatively high, so that it offers room for the accommodation of the conductors 20. It is shown in figures 2b and 3b that the width of the flat central portion 13 in the transverse direction is relatively large, compared to the width of the side ramp portions 14, 15. In the present embodiment, the cable body 10 has a smooth transition between the side ramp portions 14, 15 and the central portion 13.

[0106] The side ramp portions 14, 15 have planar contour, as they are aligned at a constant inclination angle. The side ramp portions 14, 15 have an inclination of about 20°, which inclination is defined as an angle between the side ramp portions 14, 15 of the top surface 12 and the bottom surface 11.

[0107] The top surface 12 of the cable body 10 is an anti-slip top surface, which comprises a plurality of grooves and ridges extending in the longitudinal cable direction L. The ridges protrude upwardly and are neighboured by grooves that are placed lower, compared to the ridges. The anti-slip top surface 12 therewith contributes to the safety of the cable 1, since it may reduce the risk of slipping when a passer-by would step on the cable 1 with its foot, especially in wet conditions.

[0108] In the present embodiments, the conductors 20 of the cable 1 are arranged in the cable body 10 side-by-side, parallel to the transverse direction. This enables that the cable 1 can be provided relatively flat, since the cable 1 only needs to have a height H corresponding to a single conductor 20.

[0109] The present cables 1 are three-phase vehicle charging cables, which comprise five conductors 20A, 20B, 20C, 20D, 20E. Each of the conductors 20 is formed by a plurality of electrically conductive cores that are electrically insulated from each other over the length of the cable 1 along the longitudinal cable direction L.

[0110] A first conductor 20A is formed by a first core 21 and a second core 22 and is configured to transmit a first phase.

[0111] A second conductor 20B is formed by a third core 23 and a fourth core 24 and is configured to transmit a second phase. A third conductor 20C is formed by a fifth core 25 and a sixth core 26 and is configured to transmit a third phase /

[0112] A fourth conductor 20D is formed by a seventh core 27 and an eighth core 28 and is connectable to a neutral phase.

[0113] A fifth conductor 20E is formed by a ninth core 29 and a tenth core 30, connectable to the electrical earthing.

[0114] These cables 1 are able to facilitate three-phase charging of vehicles, as it has three conductors 20A, 20B, 20C to transmit alternating-current electric power, for example having a phase shift of 120° between the phases.

[0115] According to the present embodiment, the cores 21 , 22, 23, 24, 25, 26, 27, 28, 29, 30 all have a conductive cross-sectional area of 1.5 mm2. This area was found to be optimal in balancing between height of the conductors and conductivity, for preventing overheating.

[0116] The vehicle charging cables 1 further comprise two further conductors 31 , 32, which are configured to transmit data signals between the EV charging box 100 and the electric vehicle 101. The further conductors comprise a proximity pilot (PP) line 31 , configured to establish pre-insertion signalling through the cable 1 , for example to detect if a vehicle B connector of the cable 1 is connected properly to the vehicle charging port. The further conductors also comprise a control pilot (CP) line 32, configured to establish post-insertion signalling through the cable 1, for example to monitor electric currents that are supplied to the vehicle 101.

[0117] The cable bodies 10 of both cables 1 comprise at least one central cavity 16, extending through the cable body 10 between the ends of the cable 1 in the longitudinal cable direction L. Seen in the cross-sectional plane perpendicular to the longitudinal cable direction L, as in figures 2b and 3b, the cavity 16 is provided in the centre of the cable body 10, so that the cavity 16 is inaccessible from the outside and shielded against external influences.

[0118] The conductors 20 extend through the at least one central cavity 16 and the cable body 1 comprises at least one short-circuit shielding 41 in the at least one central cavity 16 that surrounds one or more of the conductors 20.

[0119] The conductors 20 extend in the cavity 16, so that they are shielded from the outside as well. The short-circuit shielding 41 is arranged to surround the conductors 20, so that, in the event of inadvertent damaging of the cable body 10, a physical barrier may be formed around the conductors 20. To this effect, the short-circuit shielding is embodied as a wire mesh 41 around the conductors 20.

[0120] The short-circuit shielding 41 is electrically conductive and is connectable to an electrical earthing during use, so that a ground fault circuit interrupter may be activated in case one or more of the conductors 20 ends up in electrical contact with the short-circuit shielding 41 upon damaging of the cable 1. The cable 1 in figures 2a and 2b differs from the cable T in figures 3a and 3b, in that the cable body 10 in figures 2a and 2b has a plurality of cavities 16, corresponding to the number of cores 21 - 32, whereas the cable body 10’ in figures 3a and 3b has a single cavity 16’.

[0121] In the cable 1 in figures 2a and 2b, a single core 21 - 32 is arranged in each of the cavities 16. The cable 1 further comprises a plurality of short-circuit shieldings 41 - 52, corresponding to the number of cores 21 - 32 as well. Each of the shieldings 41 - 52 is arranged in a different cavity 16 to each surround a single core 21 - 32.

[0122] The cavity 16’ in the cable body 10’ in figures 3a and 3b is elongate in the transverse direction and all cores 2T - 32’ are arranged in the cavity 16’ side by side. The cable body 10’ comprises a single common short-circuit shielding 4T in the cavity 16’ that surrounds all cores 2T - 32’.

[0123] Figure 4 schematically depicts an alternative embodiment of the vehicle charging cable according to the present invention, to which is referred with reference numeral 51. The cable 51 comprises a cable body 60 with a first end 68 and an opposed second end 69. The cable further comprises a first end section 81, connected to the first end 68 of the cable body 60, and a second end section 82, connected to the second end 69 of the cable body 60. The end sections 81 , 82 have circular cross-sections that are different from the flattened cross-section of the cable body 60 in between them.

[0124] The cable 51 further comprises a first adapter element 83, arranged in between the first end section 81 and the cable body 60, and a second adapter element 84, arranged in between the second end section 82 and the cable body 60. The adapter elements 83, 84 serve as transitions between the respective end sections and the cable, in order to provide a smooth transition between their different cross-sections and to provide for improved shielding of the conductors 20 extending between the respective end portions 83, 84 and the cable body 60. The adapter elements 83, 84 are moulded around the end portions 81 , 82 and the cable body 60 by means of an injection moulding process, so that unitary adapter elements 83, 84 are provided, which accurately seal around the end portions 81, 82 and the cable body 60 and which are free of seams, in order to prevent water or dirt from entering the adapter elements 83, 84.

[0125] Both adapter elements 83, 84 are two-piece adapter elements 83, 84, each comprising a first adapter part, connected to the cable’s end section 81, 82, and a second adapter part, connected to the cable body 60. The first adapter parts are connectable to the second adapter parts to establish an electrical connection between the cable body 60 and the respective end sections 81 , 82.

[0126] In the embodiment of the cable 51 shown in figure 4, the conductors 20 also extend through the first end section 81 and the second end section 82. The number of cores 21 - 32 per conductor 20 in the cable body 60 is larger than the number of cores per conductor 20 in the first end section 81 and the second end section 82. Each of the conductors 20 consists of a single core in the first end section 81 and the second end section 82.

[0127] The conductors 20 in the cable body 60 are electrically connected to the conductors 20 in the end sections 81 , 82 in the respective adapter elements 83, 84. In these adapter elements 83, 84, the multiple cores 21 - 32 of each conductor 20 in the cable body 60 are connected to the single core of that conductor 20 in the end sections 81, 82. The adapter elements 83, 84 thereby serve the purpose of shielding the electric connection between the different cores 21 - 32 of each conductor 20 against external influences.

Claims

CLAIMS1. Cable for transmitting electric power between an electric current source and an electric current load, such as the battery of a vehicle, the cable comprising: an elongate cable body, extending substantially between two ends of the cable in a longitudinal cable direction, having a width in a first, e.g. transverse, direction perpendicular to the longitudinal cable direction and having a height in a second, e.g. vertical, direction perpendicular to the longitudinal cable direction and the first direction, and a plurality of conductors inside the cable body, extending between the ends of the cable in the longitudinal cable direction, wherein the cable body has a non-circular cross-section, in a plane perpendicular to the longitudinal cable direction, and wherein the height of the cable body is smaller than the width of the cable body.

2. Cable according to claim 1 , wherein the height of the cable body is at least five times smaller than the width of the cable body, preferably at least ten times smaller than the width of the cable body.

3. Cable according to claim 1 or 2, wherein the height of the cable body is smaller than 20 mm, preferably smaller than 10 mm, for example about 5 mm.

4. Cable according to any of the preceding claims, wherein the cable body has a substantially trapezoid cross-section.

5. Cable according to any of the preceding claims, wherein the cable body has a bottom surface, configured to be arranged on a ground, e.g. a sidewalk, during use of the cable for transmitting electric power, and wherein the cable body has a top surface, opposite to the bottom surface, which is configured to face upwards during use.

6. Cable according to claim 5, wherein the top surface has a flat central portion and side ramp portions at opposed sides of the flat central portion, which slope downwards towards the opposed sides of the cable body.

7. Cable according to claim 6, wherein the side ramp portions have an inclination of less than 45°, preferably less than 30°, for example about 20°.

8. Cable according to any of the claims 5 - 7, wherein the top surface is an anti-slip top surface, for example comprising a plurality of grooves and ridges extending in the longitudinal cable direction.

9. Cable according to any of the preceding claims, wherein the cable body comprises at least one central cavity, extending through the cable body between the ends of the cable in the longitudinal cable direction, wherein the conductors extend through the at least one central cavity, and wherein the cable body comprises at least one short-circuit shielding in the at least one central cavity that surrounds one or more of the conductors, which shielding is configured to be connected to an electrical earthing during use.

10. Cable according to claim 9, wherein the cable body comprises a single cavity, e.g. being elongate in the first direction, in which all conductors are arranged side by side, and wherein the cable body comprises a single common short-circuit shielding in the cavity that surrounds all conductors.

11. Cable according to claim 9, wherein the cable body comprises a plurality of cavities, corresponding to the number of conductors, in each of which a single conductor is arranged, and wherein the cable body comprises a plurality of short-circuit shieldings, corresponding to the number of conductors, each arranged in a different cavity to each surround a single conductor.

12. Cable according to any of the preceding claims, wherein each of the conductors is formed by a plurality of electrically conductive cores that are electrically insulated from each other over the length of the cable along the longitudinal cable direction and that are connected to each other at the ends of the cable body.

13. Cable according to claim 12, wherein the cable is three-phase cable, in particular a three-phase vehicle charging cable, comprising five conductors, wherein: a first conductor is formed by a first and a second core, configured to transmit a first phase, a second conductor is formed by a third and a fourth core, configured to transmit a second phase, a third conductor is formed by a fifth and a sixth core, configured to transmit a third phase, a fourth conductor is formed by a seventh and an eighth core, connectable to aneutral phase, and a fifth conductor is formed by a ninth and a tenth core, connectable to the electrical earthing.

14. Cable according to any of the preceding claims, further comprising a first end section, connected to the cable body at a first end thereof, and a second end section, connected to the cable body at a second end thereof, wherein the first end section and the second end section have a cross-section different from the cable body, for example having a circular cross-section.

15. Cable according to claim 14, further comprising a first adapter element, arranged in between the first end section and the cable body, and a second adapter element, arranged in between the second end section and the cable body.

16. Cable according to claim 15, wherein one or both of the adapter elements are two-piece adapter element, each comprising a first adapter part, connected to the respective end section, and a second adapter part, connected to the cable body.

17. Cable according to any of the claims 14 - 16, wherein the conductors also extend through the first end section and the second end section, and wherein, for at least one of the conductors, the number of cores per conductor in the cable body differs from the number of cores per conductor in the first end section and / or the second end section.

18. Cable according to claim 17, wherein each of the conductors consists of a single core in the first end section and / or the second end section.

19. Cable according to any of the preceding claims, wherein the cable body is made from an elastomeric material, for example comprising a polyurethane (Pll) material or ethylene propylene diene monomer (EPDM) rubber.

20. Method of transmitting electric power between an electric current source and an electric current load, such as the battery of a vehicle by means of a cable according to any of the preceding claims, comprising the steps of: electrically connecting the cable to the electric current source with a first end, electrically connecting the cable to the electric current load, e.g. the vehicle with a second end, and establishing an electric current between the electric current source and the electric current load, e.g. the vehicle.

Images