Patent Description:
This arrangement is used for example to supply power to excavators and other work machines. In operation, the cable or tether may be placed under tension if the machine moves too far from the power supply point or if the cable becomes tangled in moving parts of the machine.

To address this problem it is known to monitor the tension in the cable, or to disconnect the power supply so that the machine is brought to a stop when the cable is stretched.

For example, <CIT> discloses an electric excavator with a swivelling tether support arm. A power cable is plugged into a socket on the arm, and supported at a short distance from the arm by an elastic strain reliever attached to the arm. A slack portion of the cable extends alongside the elastic strain reliever, which relieves the plug and socket connection from tension in the cable. A tension sensor is arranged to monitor the connection by sensing tension in the elastic strain reliever.

<CIT> discloses a power supply vehicle which supplies power to a moving machine via a retractable cable. The cable is connected to a cable disconnection device mounted on a swivelling arm attached to the machine. The cable disconnection device disconnects the cable when a tension sensor detects excessive tension in the cable. The cable may terminate at a plug which is received in a socket on the rotating arm and retained by a brittle pin which allows the plug to detach from the socket under excessive tension. The power supply vehicle automatically turns off the power supply to the cable when the cable is disconnected from the machine <CIT> describes a safety apparatus and method for preventing accidental damage to trailing cable power conductors connected between a power source and an electrically driven vehicle such as mining equipment or the like.

In any practical system, it is desirable to ensure that the power supply is not interrupted by nuisance operation of the safety mechanism. For example, where a considerable length of power cable is suspended to form a catenary curve, the cable forms an elastic system, and its weight may cause intermittent operation of the safety mechanism if set in oscillation by a sudden movement of the machine.

With practice, an operator may choose to operate the machine in such conditions close to the limit of the cable. It would be useful to discourage such operator behaviour in order to avoid fatiguing the cable and power connectors.

A plug and socket connection may be configured to detach under excess load while resisting nuisance operation. However, damaging arcing may occur at the contacts on detachment of the plug, while the detached plug could be hazardous, for example, if it falls into water while the conductor is live. Moreover, connective parts that are configured to pass high currents require a substantial mechanical joint which may resist disconnection, especially if the disconnection force is not exactly aligned with the connection axis. In such situations, a suddenly applied tension force could damage the cable before disconnection occurs.

Once the power supply is interrupted the machine will undergo some residual motion before it comes to rest. It would be desirable to ensure that the residual motion of the machine cannot further strain the cable to breaking point, in the event that the cable should become entangled in parts that undergo substantial residual motion due to a large momentum - for example, if the machine happens to be operating with a fully loaded bucket at the end of a fully extended boom and stick.

The invention is as defined in independent assembly claim <NUM> and independent method claim <NUM>.

In a first aspect, the disclosure provides an assembly for supplying power to a vehicle.

The assembly includes a power cable having a first end connectable to an electric power supply, and a second end connectable to a vehicle to supply electric power from the power supply to the vehicle; and a disconnection switch, operable to interrupt the supply of electric power from the cable to the vehicle.

The assembly further includes an anchor, connected to the cable between its first and second ends, to define a first portion of the cable extending between the anchor and the first end of the cable, and a second portion of the cable extending between the anchor and the second end of the cable; and a mount configured to be supported on the vehicle in a use position.

In the use position of the mount, when the second end of the cable is connected to the vehicle, the anchor is detachably attachable and re-attachable to the mount, to support the cable on the mount with the second portion of the cable in a slack condition.

The anchor is detachable from the mount by application of a threshold detachment force by tension in the first portion of the cable, and the disconnection switch is operable by detachment of the anchor from the mount to interrupt the supply of electric power.

In a related aspect, the disclosure provides a vehicle including the assembly, wherein the second end of the cable is connected to the vehicle and the mount is supported on the vehicle in the use position.

In another aspect, the disclosure provides a method of supplying electric power to a vehicle, including: providing a power cable; arranging a first end of the cable to be connectable to an electric power supply, and a second end of the cable to be connectable to the vehicle to supply electric power from the power supply to the vehicle; and arranging a disconnection switch to be operable to interrupt the supply of electric power from the cable to the vehicle.

The method further includes: connecting an anchor to the cable between its first and second ends, to define a first portion of the cable extending between the anchor and the first end of the cable, and a second portion of the cable extending between the anchor and the second end of the cable; and supporting a mount on the vehicle in a use position, wherein the anchor is detachably attachable and re-attachable to the mount, to support the cable on the mount with the second portion of the cable in a slack condition.

The method further includes: arranging the anchor to be detachable from the mount by application of a threshold detachment force by tension in the first portion of the cable; and arranging the disconnection switch to be operable by detachment of the anchor from the mount to interrupt the supply of electric power.

Further features and advantages will be evident from the following illustrative embodiment which will now be described, purely by way of example and without limitation to the scope of the claims, and with reference to the accompanying drawings, in which:.

Referring to <FIG>, the assembly includes a power cable <NUM> having a first end <NUM> which is connectable to an electric power supply <NUM>, and a second end <NUM> which is connectable to a vehicle <NUM> to supply electric power from the power supply <NUM> to the vehicle <NUM>.

The power supply <NUM> may be a fixed power supply, and the first end <NUM> of the cable or tether <NUM> may be provided with a plug <NUM> for connection to the fixed power supply <NUM>, as shown in <FIG>. The power supply <NUM> may be, for example, a three-phase, 415V power supply. The second end <NUM> of the cable <NUM> may be provided with another electrical connector (e.g. a plug <NUM> as shown) for connection to a power intake socket <NUM> of the vehicle.

In the illustrated embodiment, the vehicle <NUM> is a work machine (work vehicle), which is to say, a vehicle that is equipped with a tool mounted on the vehicle and manipulable by the operator. The illustrated work vehicle is a small excavator, with a bucket mounted on a stick and boom, but the assembly could equally be used on other vehicles, including wheeled or tracked work vehicles.

An anchor <NUM> is connected to the cable <NUM> between its first and second ends <NUM>, <NUM>, to define a first portion <NUM> of the cable extending between the anchor <NUM> and the first end <NUM> of the cable, and a second portion <NUM> of the cable extending between the anchor <NUM> and the second end <NUM> of the cable. In this specification, the term "anchor" is used to mean a part that mechanically supports the cable.

The assembly further includes a disconnection switch <NUM> (shown in <FIG>, <FIG>), which is operable to interrupt the supply of electric power from the cable <NUM> to the vehicle <NUM>.

The disconnection switch <NUM> may be incorporated into the mount <NUM>, as exemplified by the illustrated embodiment and further described below, and may be electrically connected in-between the second end <NUM> of the cable and the powered systems <NUM> of the vehicle <NUM>, in which case it will carry the full power of the cable <NUM>. Alternatively, the disconnection switch may be arranged to control a circuit breaker which is electrically connected in-between the second end <NUM> of the cable and the powered systems <NUM> of the vehicle, in which case it may only carry a small current to control the circuit breaker, as further described below.

Alternatively the disconnection switch could be incorporated into the anchor <NUM>. In such arrangements (not shown) the disconnection switch could be electrically connected in-between the first and second portions <NUM>, <NUM> of the cable <NUM> to carry the full power of the cable. Alternatively, it could be electrically connected (e.g. via a control cable running along the second portion <NUM> of the power cable <NUM>) to a circuit breaker which is controlled by the disconnection switch and is electrically connected in-between the second end <NUM> of the cable and the powered systems <NUM> of the vehicle.

The first and second portions <NUM>, <NUM> of the cable <NUM> may be portions of a single, unbroken length of cable <NUM>, in which case, the anchor <NUM> may be clamped onto the cable, e.g. by screwing together two parts <NUM>, <NUM> of the anchor <NUM> as shown in <FIG> to secure the cable in-between them. Alternatively, the first and second portions <NUM>, <NUM> of the cable <NUM> may be two separate lengths of the cable, of similar or different construction, which are electrically connected together at the anchor, optionally with the disconnection switch being electrically interposed between them.

The assembly further includes a mount <NUM>, which is configured to be supported on the vehicle <NUM> in a use position, as shown in <FIG> and <FIG> and in <FIG>.

Referring now to <FIG>, in the use position of the mount <NUM>, when the second end <NUM> of the cable <NUM> is connected to the vehicle <NUM>, the anchor <NUM> is attachable to the mount <NUM>, and is also detachable from the mount <NUM> and re-attachable to the mount after detachment. When attached to the mount <NUM>, the anchor <NUM> supports the cable <NUM> on the mount <NUM> - which is to say, the cable <NUM> is supported by the anchor <NUM>, and the anchor <NUM> is supported by the mount <NUM> - with the second portion <NUM> of the cable in a slack condition, as shown in <FIG>. The slack, second portion <NUM> of the cable may hang in a loop, as shown. The cable <NUM> may be suspended in use from the anchor <NUM>.

The anchor <NUM> is detachable from the mount <NUM> by application of a threshold detachment force Fd by tension in the first portion <NUM> of the cable <NUM>, without mechanically disconnecting the second end <NUM> of the cable from the vehicle <NUM>. In this context, detachment of the anchor <NUM> means that the anchor is physically separated from the mount <NUM>, i.e. moved away from the mount <NUM>; after detachment, the anchor remains mechanically connected to the vehicle <NUM> by the second portion <NUM> of the cable.

Referring now to <FIG>, the disconnection switch <NUM> is operable, by detachment of the anchor <NUM> from the mount <NUM>, to interrupt the supply of electric power from the cable <NUM> to the vehicle <NUM>.

The disconnection switch <NUM> may be manually operable to re-establish the supply of electric power by re-attachment of the anchor <NUM> to the mount <NUM>. Thus, the switch may re-establish the supply of power, only when the anchor <NUM> is replaced in its attached position on the mount <NUM>.

The switch <NUM> may be a momentary switch, resiliently biased to a rest position, and may be operable by abutment against the anchor <NUM> as the anchor <NUM> moves from a detached position (<FIG>) to an attached position (<FIG>), as exemplified by the illustrated embodiment. In the example shown, the switch <NUM> is normally-open, but it could alternatively be normally-closed, depending on how the circuit is arranged.

Other switching arrangements are possible; for example, the switch could be any suitable switch or other sensor configured to interrupt the power supply (either directly or indirectly) and operable by contact or by proximity of the anchor, e.g. by a magnetic field of the anchor.

In the illustrated embodiment, the disconnection switch <NUM> is arranged to control a circuit breaker <NUM>. The circuit breaker <NUM> is arranged electrically in-between the second end <NUM> of the cable <NUM> and the powered systems <NUM> of the vehicle <NUM> to interrupt the supply of power from the cable to the vehicle. The powered systems <NUM> of the vehicle may include, for example, one or more drive motors for driving the wheels or tracks to move the vehicle <NUM> over the ground, and/or one or more actuators for controlling the boom, stick, and/or bucket or other tool.

In order to prevent unintended motion of the vehicle <NUM> responsive to replacing the anchor on the mount, the vehicle may include a control system <NUM> including a reset control <NUM> which is operable by a user separately from the disconnection switch <NUM>. The control system <NUM> is arranged to maintain the vehicle <NUM> in a disabled condition, after re-establishment of the supply of electric power, until a user input is received via the reset control <NUM>. Once the user input is received, the control system <NUM> re-enables operation of the vehicle <NUM>.

As shown in <FIG>, the control system <NUM> may include an electronic control unit <NUM> that operates another circuit breaker <NUM> to interrupt the power supply, or may be any other, e.g. electrical or mechanical arrangement, effective to disable operation of the vehicle as generally known in the art.

In this way the control system <NUM> may be configured to maintain the vehicle <NUM> in an inactive condition responsive to power loss, and to require a reset command from the operator in order to restore the vehicle <NUM> to an active condition after power is restored.

Referring again to <FIG>, the assembly may include a support structure <NUM>. The support structure <NUM> includes a swivel assembly <NUM> and an arm <NUM> supported on the swivel assembly <NUM>. The swivel assembly <NUM> is configured to be supported on the vehicle <NUM>, as shown in <FIG>, and defines a swivel axis Xs acollinear with the arm <NUM> (which is to say, not collinear with the arm - i.e. the arm <NUM> extends laterally away from the swivel axis Xs). The mount <NUM> is supported in the use position at a distal end of the arm <NUM> and is pivotable about the swivel axis Xs by movement of the arm <NUM>.

The arm <NUM> may be configured to be releasably locked in an outwardly extending position so as to hold the cable <NUM> clear of the vehicle <NUM>, for example, by manual operation of a lock <NUM>. The lock <NUM> may be configured to engage a static upright post <NUM> of the support structure while the arm <NUM> swivels around the post <NUM> on an internal joint, as shown. Conveniently, the arm <NUM> may be configured to support the cable in a coil on the arm when the vehicle is not in use.

The second end <NUM> of the cable <NUM> may be releasably coupled to a power connector, such as an intake socket <NUM> as shown, which is mounted on the support structure <NUM>. Optionally, another mechanical support (not shown) may be provided at the second end <NUM> of the cable to relieve the power connection, e.g. plug <NUM> and intake socket <NUM>, from tension in the second portion <NUM> of the cable when the anchor <NUM> is detached from the mount.

Referring to <FIG>, the anchor <NUM> may be detachable from the mount <NUM> in its use position by movement of the anchor <NUM> along a detachment axis Xd of the mount. The anchor <NUM> and mount <NUM> may define co-operating abutment surfaces <NUM>, <NUM> which are configured to convert a tension force Ft applied by the first portion <NUM> of the cable in a direction not aligned with the detachment axis Xd, to generate a force component (represented in <FIG> by the detachment force Fd) acting along the detachment axis Xd.

As shown in <FIG>, the tension force Ft may be applied in different directions to the mount <NUM> (which reacts the tension force applied by the cable <NUM> to the anchor <NUM>), depending on how the vehicle <NUM> moves over the ground relative to the fixed location of the power supply <NUM>. In order to ensure reliable detachment when the cable is tensioned, irrespective of its orientation, the abutment surfaces <NUM>, <NUM> may be configured to generate a force component (Fd) acting along the detachment axis Xd when the tension force Ft acts in a direction normal to the detachment axis Xd, illustrated by the uppermost position of the cable <NUM> as shown in broken lines in <FIG>. The force component Fd may be generated by selecting a suitable contact angle between the abutment surfaces, relative to their coefficient of friction, to generate sliding or pivotal motion between them as known in the art. For this purpose the mount <NUM> may define a shallow, inwardly tapering recess which receives the anchor. The recess may be downwardly facing to further ensure reliable detachment, as further discussed below.

As illustrated in <FIG>, the abutment surfaces <NUM>, <NUM> may be configured to generate a force component (Fd) acting along the detachment axis Xd when the tension force Ft acts in either of two opposite directions normal to the detachment axis Xd, represented by the two opposite directions of the cable <NUM> as shown in broken lines in <FIG>. This ensures detachment when the vehicle <NUM> is oriented anywhere in a wide angular range relative to the direction of the cable <NUM>, and especially when the arm <NUM> is locked so that it cannot swivel.

As best seen in <FIG>, the co-operating abutment surfaces <NUM>, <NUM> may be surfaces of rotation, e.g. frustoconical surfaces, to ensure reliable detachment under a tension force Ft applied through a wide angular range. A curved or radiused profile may alternatively be used.

The anchor <NUM> may be magnetically attachable to the mount <NUM>, for example, by arranging a magnet <NUM> (or two or more magnets) in the anchor <NUM> to be attracted to a magnet-responsive material (e.g. another magnet, or an iron or steel body <NUM>) in the mount <NUM>. Alternatively the mount may include a magnet or magnets that attract the anchor. The magnets may be configured to exert an attraction force that declines rapidly with increasing distance between the anchor <NUM> and the mount <NUM>, and so may define a relatively short threshold distance Dt (<FIG>) as discussed below.

Alternatively, a mechanical catch (not shown) could be arranged to release the anchor at the threshold detachment force. For example, the catch could be urged into engagement with the anchor (or with the mount) by a resilient bias element, until it is released when the threshold detachment force overcomes the restoring force of the resilient bias element.

As exemplified by the illustrated embodiment, the anchor <NUM> may be attachable to a downwardly facing portion <NUM> of the mount <NUM> in its use position. The downwardly facing portion <NUM> of the mount may define a downwardly open recess <NUM>, with the anchor <NUM> being received in the recess <NUM> when attached to the mount <NUM>. The recess <NUM> helps to locate the anchor <NUM> on the mount. Alternatively, the anchor <NUM> could include a recess which receives a downwardly facing protuberance of the mount.

Further as exemplified by the illustrated embodiment, the anchor <NUM> may include a handgrip <NUM>, which is arranged on a downwardly facing side of the anchor <NUM> when the anchor <NUM> is attached to the mount <NUM> in the use position of the mount, as shown in <FIG> and <FIG>. The anchor <NUM> may comprise a moulded body (e.g. of plastics or aluminium) on which the handgrip is integrally formed.

Referring to <FIG>, the assembly may be arranged so that, in the downwardly facing, use position of the mount <NUM>, when the anchor <NUM> is separated from the mount <NUM> by a threshold distance Dt along the detachment axis Xd of the mount, the anchor <NUM> is further separable from the mount by a net separating force (represented in <FIG> by the detachment force Fd) acting along the detachment axis Xd and equivalent to the self weight of the anchor <NUM> and the second portion <NUM> of the cable. The threshold distance Dt may be not more than <NUM>.

In addition, in the use position of the mount <NUM>, when the anchor <NUM> is separated from the mount <NUM> by half of the threshold distance Dt along the detachment axis Xd, the anchor <NUM> and the mount <NUM> may co-operate to apply an attraction force to the anchor, acting along the detachment axis Xd and of a magnitude greater than said net separating force, to urge the anchor <NUM> towards the mount <NUM>. The attraction force acts in the opposite direction to the detachment force Fd as shown in <FIG>, and assists the user in re-attaching the anchor <NUM> against its own weight and the weight of the suspended cable <NUM>.

For example, a magnet <NUM> or magnets may exert an attraction force to urge the anchor <NUM> into its mounted position as it approaches very close to the mount <NUM> at less than one half of the threshold distance Dt - for example, within the last <NUM> or <NUM> of movement. Alternatively, if the assembly includes instead of a magnet, a resilient (e.g. spring biased) catch mechanism (not shown) to retain the anchor to the mount, the catch may pass, reversibly, through a metastable or over-centre position as the anchor approaches very close to the mount, e.g. within the last <NUM> or <NUM> of movement, after which the bias spring acts on the catch to urge the anchor towards the mount.

Where the disconnection switch <NUM> is resiliently biased to the disconnected state (i.e. to the position in which it acts to interrupt the power supply), the attraction force may overcome the resilient bias to move the disconnection switch <NUM> to the connected state to re-establish the power supply, as shown in <FIG>.

After detachment of the anchor <NUM> from the mount <NUM>, the effective length of the cable <NUM> is immediately increased by the additional length provided by the slack, second portion <NUM> of the cable, as shown in <FIG>. This immediately reduces tension in the cable <NUM>, while accommodating a small range of further movement of the vehicle <NUM> as the vehicle comes to rest after power is lost, preventing damage to the cable.

After detachment, the anchor <NUM> remains mechanically connected to the vehicle <NUM> by the second portion <NUM> of the cable. This ensures that the second end <NUM> of the cable does not present an electrical hazard if the cable <NUM> remains live after disconnection, and further assists the operator to re-attach the anchor <NUM> to the mount <NUM>.

The length of the slack, second portion <NUM> of the cable may be selected to increase the effective length of the cable <NUM> by an additional length greater than a maximum range of residual movement of the vehicle <NUM> as the vehicle comes to rest following a loss of power. The maximum residual movement may be greatest at a distal extremity of a work tool mounted on the vehicle, e.g. at the tip of the bucket.

Typically, it will be difficult for the user to replace the anchor <NUM> in its attached position without relieving tension in the cable <NUM>. So, in order to replace the anchor <NUM>, the operator must disentangle the cable <NUM> if it is entangled, or, if it is overextended but not entangled, must provide a longer cable <NUM>.

The disconnection switch <NUM> may be configured to reset to the functional condition only when the anchor <NUM> is replaced in its attached position on the mount <NUM>. Since it is difficult to replace the anchor <NUM> without sorting out the problem with the cable, this effectively precludes reconnection in an unsafe condition of the cable. For example, the switch <NUM> may be a momentary switch, as exemplified by the illustrated embodiment.

Moreover, since the operator is required to go to the anchor <NUM> to manually replace the anchor in its attached position, this prevents the operator from resetting the power supply to the vehicle <NUM> without a proper inspection of the cable <NUM> where it connects to the vehicle. The necessity of attending the anchor <NUM> to reset the system also discourages the operator from operating the machine close to the maximum stretched limit of the cable.

In combination, the automatic reset of the disconnection switch <NUM> and the inhibitory operation of the control system <NUM> provide a simple, two-step procedure to resume operation of the vehicle after the power supply is disconnected, while ensuring that the vehicle <NUM> cannot be re-started until the operator is ready to resume control.

The threshold distance Dt represents the inverse relationship between the force required to move the anchor <NUM> further away from the mount <NUM>, and the distance of the anchor from the mount. The net separating force is the total force acting on the anchor along the detachment axis Xd. For example, if the detachment axis Xd is vertical as shown, and the anchor <NUM> together with the second portion <NUM> of the cable weighs <NUM>, then a net separating force of 1kgf acting vertically downwardly will move the anchor <NUM> further away from the mount <NUM> when the anchor <NUM> is at or beyond the threshold distance Dt from the mount <NUM>. The threshold distance Dt can be determined experimentally by removing the anchor <NUM> from the cable <NUM> and supporting the anchor <NUM>, with a weight representing the mass of the second portion <NUM> of the cable, at the threshold distance from the mount <NUM> along the detachment axis Xd.

Of course, in use, the anchor <NUM> will also support the weight of the first portion <NUM> of the cable, which will vary depending on its suspended length and diameter, and so the net separating force and the attraction force (if provided) can be selected accordingly to suit the intended operating conditions of the vehicle <NUM>. It is conceivable also that the net separating force and/or the attraction force may be adjustable to suit different operating conditions. This could be achieved for example in a magnetic coupling system by positioning an adjustable spacer, e.g. a shim set of variable thickness, between the anchor <NUM> and the mount <NUM>, or in a system based on a spring catch mechanism, by adjusting the strength (e.g. compression) of the retaining spring that energises the catch that engages the anchor to retain the anchor to the mount.

It will be understood that a short threshold distance Dt means a more sudden, bistable action, and a reduced window for metastable operation - which is to say, it makes it more difficult for the user to operate the vehicle <NUM> with the cable <NUM> at maximum tension. As soon as the tension in the cable <NUM> rises to a level sufficient to apply the threshold detachment force Fd, the anchor <NUM> will detach suddenly and then fall away from the downwardly facing mount <NUM> under its own weight and the weight of the first and second portions of the cable <NUM>.

In order to further accentuate this bistable action, the threshold distance may be reduced to less than <NUM>, less than <NUM>, or even less than <NUM>.

In order to further assist the user in re-attaching the anchor <NUM>, the magnitude of the attraction force may be more than two times the net separating force, or even more the four times the net separating force.

In order to avoid nuisance operation when supporting a long and heavy cable <NUM>, the threshold detachment force may at least five times the net separating force, optionally at least ten times the net separating force, or even at least fifteen times the net separating force.

For example, the threshold detachment force could be at least 5kgf, at least 10kgf, or even at least 15kgf.

In summary, an electric vehicle <NUM> is supplied with power from a power supply <NUM> via a cable <NUM> supported by an anchor <NUM>. The anchor <NUM> is attached to a mount <NUM> on the vehicle and detachable from the mount <NUM> by tension in a first portion <NUM> of the cable between the anchor <NUM> and the power supply <NUM>. A second portion <NUM> of the cable between the anchor <NUM> and the vehicle <NUM> remains slack in the attached position of the anchor <NUM>, and extends on detachment of the anchor to relieve tension in the first portion <NUM> of the cable <NUM>. A disconnection switch <NUM> is operable by detachment of the anchor <NUM> to interrupt the power supply from the cable <NUM> to the vehicle <NUM>.

In use, the vehicle <NUM> may be supplied with electric power by providing a power cable <NUM> and arranging a first end <NUM> of the cable to be connectable to an electric power supply <NUM>, and a second end <NUM> of the cable to be connectable to the vehicle to supply electric power from the power supply <NUM> to the vehicle <NUM>.

The method further includes arranging a disconnection switch <NUM> to be operable to interrupt the supply of electric power from the cable <NUM> to the vehicle <NUM>, and connecting an anchor <NUM> to the cable between its first and second ends <NUM>, <NUM>, to define a first portion <NUM> of the cable extending between the anchor <NUM> and the first end <NUM> of the cable, and a second portion <NUM> of the cable extending between the anchor <NUM> and the second end <NUM> of the cable.

The method further includes supporting a mount <NUM> on the vehicle <NUM> in a use position, wherein the anchor <NUM> is detachably attachable and re-attachable to the mount <NUM>, to support the cable <NUM> on the mount <NUM> with the second portion <NUM> of the cable in a slack condition.

The method further includes arranging the anchor <NUM> to be detachable from the mount <NUM> by application of a threshold detachment force Fd by tension in the first portion <NUM> of the cable, and arranging the disconnection switch <NUM> to be operable by detachment of the anchor <NUM> from the mount <NUM> to interrupt the supply of electric power from the cable <NUM> to the vehicle <NUM>.

Many further adaptations are possible within the scope of the claims.

Claim 1:
An apparatus for supplying power to a vehicle (<NUM>), including:
a power cable (<NUM>) having a first end (<NUM>) connectable to an electric power supply (<NUM>) and a second end (<NUM>) connectable to a vehicle (<NUM>) to supply electric power from the power supply (<NUM>) to the vehicle (<NUM>);
a disconnection switch (<NUM>), operable to interrupt the supply of electric power via the cable (<NUM>) to the vehicle (<NUM>);
an anchor (<NUM>), connected to the cable (<NUM>) between its first and second ends (<NUM>, <NUM>), to define a first portion (<NUM>) of the cable (<NUM>) extending between the anchor (<NUM>) and the first end (<NUM>) of the cable, and a second portion (<NUM>) of the cable (<NUM>) extending between the anchor (<NUM>) and the second end (<NUM>) of the cable; and
a mount (<NUM>) configured to be supported in a use position; wherein,
in the use position of the mount (<NUM>), when the second end (<NUM>) of the cable (<NUM>) is connected to the vehicle (<NUM>), the anchor (<NUM>) is detachably attachable and re-attachable to the mount (<NUM>), to support the cable (<NUM>) on the mount (<NUM>) with a respective said portion of the cable (<NUM>) in a slack condition; and wherein
the anchor (<NUM>) is detachable from the mount (<NUM>) by application of a threshold detachment force (Fd) by tension in a respective said portion of the cable (<NUM>); and
the disconnection switch (<NUM>) is operable by detachment of the anchor (<NUM>) from the mount (<NUM>) to interrupt the supply of electric power;
characterised in that
the mount (<NUM>) is configured to be supported on the vehicle (<NUM>) in the use position, and
the disconnection switch (<NUM>) is operable to interrupt the supply of electric power from the cable (<NUM>) to the vehicle (<NUM>); and
in the use position of the mount (<NUM>), when the second end (<NUM>) of the cable (<NUM>) is connected to the vehicle (<NUM>), the anchor (<NUM>) is detachably attachable and re-attachable to the mount (<NUM>), to support the cable (<NUM>) on the mount (<NUM>) with the second portion (<NUM>) of the cable (<NUM>) in said slack condition; and
the anchor (<NUM>) is detachable from the mount (<NUM>) by application of the threshold detachment force (Fd) by tension in the first portion (<NUM>) of the cable (<NUM>).