The present invention relates to a collision safety system for an electric vehicle, and in particular a collision detection device for a mobility scooter.

A mobility scooter is an electrically powered scooter designed for people with restricted mobility. Typical users of a mobility scooter are elderly or disabled people. Mobility scooters are divided into class 2 and class 3 vehicles. Class 2 scooters are limited up to 4mph and in general are designed for pavement use. Class 3 scooters have a maximum speed of up to 8mph for road use, and include a switch to reduce the maximum speed to 4mph so they can be used on a pavement. Class 3 scooters tend to be larger and heavier.

All classes of mobility scooters have certain basic controls in common. An on/off switch, which may be key operated, is used to operate the scooter, and acceleration is controlled by a simple lever. The lever is pushed in a first direction to move the scooter forward, and in a second direction to reverse.

Class 2 scooters are not provided with conventional user operated brakes, and in order to stop the user must release the accelerator lever. As soon as the user stops pressing the accelerator lever the throttle is disengaged and the brakes automatically activate to bring the scooter to a stop. This is referred to as passive braking and the braking system is configured to activate even if power to the scooter is cut. However, the action of passive braking can be difficult to get used to as it is counterintuitive and is the opposite of the way in which a bike is stopped for example. These difficulties in braking can lead to accidents. For example, the user may simply be too slow to react when a collision is imminent. It has also been found that user's panic before a collision and instead of releasing the accelerator they grip it in a conventional 'braking' action, which not only prevents the scooter from stopping but makes it accelerate and lurch forward making the collision worse. In certain cases where pedestrians have been hit by a mobility scooter, the user's impulse to grip the brake results not only in a collision with the pedestrian, but also in the pedestrian being driven several meters forward until the scooter comes to a halt. As such, the injuries incurred as a result of the collision can be far worse.

It is therefore desirable to provide an improved braking system for a mobility scooter which addresses the above described problems and/or which offers improvements generally.

According to the present invention there is provided a collision safety device for a mobility scooter, and an electrical vehicle such as a mobility scooter as described in the accompanying claims.

In an aspect of the invention there is provided a collision safety system for a mobility scooter comprising an electrical circuit including a connector for connecting the electrical circuit to a mobility scooter immobiliser; and a collision detector configured to detect a collision and/or an object within a predetermined safety range indicative of a potential collision and to close the electrical circuit in response to said collision or detected object to in use cause the immobiliser connected thereto to stop the mobility scooter. A collision detector is any device configured to detect a collision or a potential collision. This includes contact detectors such as a bumper switch, non-contact detectors such as ultrasonic detectors, or a combination of both. The collision detector may comprise more than one detector or sensor device. Specifically, the connector is configured for connecting the electrical circuit to the charging socket of a mobility scooter which is in electrical connection with an immobiliser/inhibitor of the scooter.

The connector is a detachable connector such as a three-pin plug that is connectable with and removable from the corresponding connector of the mobility scooter, which may be a socket corresponding to and configured to receive the plug. The term 'receive' is intended to encompass receipt within, around or against the corresponding connector or in any way which forms a suitable electric connection between the two connectors. In an embodiment of the invention there is provided a collision switch for a mobility scooter. The collision switch comprises a bumper member including a contact surface, the bumper member being configured to be mounted to a mobility scooter such that contact surface is outwardly facing and arranged to be impacted during a collision. The collision also includes first and second electrical contacts and an electrical circuit connected to the first and second electrical contacts such that separation of the first and second electrical contacts creates a break which opens the electrical circuit. The electrical circuit includes a connector for connecting the electrical circuit to a mobility scooter immobiliser. The bumper member is configured such that when mounted to a mobility scooter it is movable relative to the mobility scooter from an expanded configuration to a compressed configuration when the outer surface is engaged during a collision, and wherein the first and second electrical contacts are arranged such that when the bumper is in the expanded position the first and second electrical contacts are separated to open the electrical circuit, which in use permits movement of the mobility scooter, and when the bumper is in the compressed position the first and second electrical contacts are in contact to close the electrical circuit, which in use immobilises the mobility scooter. The bumper member is moved to the compressed configuration during a collision and movement of the bumper member to the compressed configuration causes the scooter to be immobilised, which mitigates the injury and/or damage caused during the collision.

The collision switch may comprise a support member configured to be mounted to a mobility scooter, and the bumper member may connected to the support member such that it is movable in a rearwards direction towards the support member and a forwards direction away from the support member, the bumper member moving rearward ly to the compressed configuration and forwardly to the expanded configuration. The bumper member and support member form part of a switch assembly configured to be mounted to scooter as a single unit, which enables the switch to be easily retro fitted to existing scooters.

The first electrical contact may be located on the support member and the second electrical contact may be located on the bumper member. The support member is preferably configured such that when mounted to the mobility scooter in use it is fixed in position relative to the mobility scooter. The support member is thereby used to mount the switch to the scooter, and to support the bumper member.

The support member and the bumper member may each have an inner surface and an outer surface that faces forwardly away from the mobility scooter in use, the inner surface of the bumper member and the outer surface of the support member face each other, and the first electrical contact is located on the outer surface of the support member and the second electrical contact is located on the inner surface of the bumper member. The bumper member moves rearwardly towards the support member with the forward and rearward direction being defined relative to the forward direction of travel of the scooter. It will however be appreciated that the collision switch could alternatively or in addition be mounted to the rear of the scooter.

The collision switch may comprise at least one biasing member arranged to bias the bumper member away from the support member to the expanded configuration. The biasing members hold the bumper in the expanded configuration and return it to the expanded configuration following compression.

The bumper member may be mounted to the support member by at least one guide member, and the bumper member may be slidable along the at least one guide member to move between the expanded and compressed configurations in the forward and rearward direction. Preferably a plurality of guide members are provided that extend in the forward/rearward direction.

Preferably the bumper member and support member comprise metal bars or plates

The bumper member preferably comprises an electrically conductive core at least partially covered by an insulating layer, and the second electrical contact comprises at least one electrically conductive projection connected to the core of the bumper member and extending rearward ly from the bumper member towards the support member, and wherein the first electrical contact is aligned with the at least one projection and the first and second electrical contacts are arranged such that the at least one projection is spaced from the first electrical contact in the expanded configuration and such that the at least one projection contacts the first electrical contact in the compressed configuration.

The biasing member may be at least one spring arranged about the at least one projection, and the at least one projection is surrounded by at least one electrically insulating sleeve located between the at least one projection and the at least one spring.

The second electrical contact may comprise a plurality of projections extending rearward ly from the bumper member and the first electrical contact comprises a plurality of first electrical contacts arranged on the outer surface of the support member and aligned with the plurality of second electrical contacts.

The support member may comprise an electrically conductive core and an electrically insulating layer at least partially covering the core, and the plurality of first electrical contacts are in electrical contact with the core of the support member.

In another aspect of the invention there is provided an electric vehicle such as a mobility scooter having a vehicle body and comprising a collision switch as described above mounted to the vehicle body such that the bumper member is contacted in the event of a collision, wherein the vehicle comprises a drive motor and an immobiliser arranged to immobilise the vehicle by preventing operation of the drive motor and/or by activating the brakes, and the electrical circuit is connected to the immobiliser to cause the immobiliser to prevent operation of the drive motor when the bumper member is in the compressed configuration and the electrical circuit is closed.

The electric vehicle may comprise a battery and a charging socket for charging the battery, and the immobiliser is connected to the charging socket such that the immobiliser is activated to immobilise the vehicle when a closed electrical circuit is connected to the charging socket, and the electrical circuit of the collision switch is connected to the charging socket.

The vehicle preferably has a front end which faces forwardly relative to the direction of travel and the collision switch is mounted to the front end of the vehicle and arranged such that the bumper element is the foremost part of the vehicle.

The electrical circuit is preferably connected to an intermediate socket mounted to the vehicle body, and the intermediate socket is connected to the charging socket via a secondary cable having a first plug compatible with the charging socket and a second plug compatible with the intermediate socket.

In another aspect of the invention there is provided an electric vehicle such as a mobility scooter comprising a collision safety system according to any preceding claim wherein the vehicle comprises a drive motor, an immobiliser arranged to prevent operation of the drive motor, and an electrical connector connected to the immobiliser and configured to receive the connector of the collision safety system to connect the immobiliser to the electrical circuit of the collision safety system and wherein when the electrical circuit of the collision safety system connected to the immobiliser is closed the immobiliser prevents operation of the drive motor to stop the vehicle.

The electrical connector of the electric vehicle may be a charging connector that is connected to an electric power storage device of the electric vehicle in addition to the immobiliser, and is configured to receive an electrical connector of a charging device, the immobiliser being configured to immobile the vehicle when the charging device is connected to the electrical connector of the electric vehicle.

The electrical connector of the collision safety system and the electrical connector of the charging device are preferably interchangeably receivable by the charging connector of the electric vehicle, meaning that both connectors may be received by the charging connector of the vehicle and one may be inserted when the other is removed. The vehicle preferably comprises a battery and a charging socket for charging the battery, and the immobiliser is operatively connected to the charging socket such that the immobiliser is activated to immobilise the vehicle when the electrical circuit of the collision switch is connected to the charging socket in a closed state, meaning it is activated when the connector is received by the charging socket and, while received, the electrical circuit of the collision switch is closed.

The present invention will now be described by way of example only with reference to the following illustrative figures in which:

Figure 1 shows a collision switch according to the present

invention in the expanded configuration; and

Figure 2 shows a collision switch according to the present

invention in the compressed configuration.

Referring to Figure 1, an emergency stop device for a mobility scooter is shown in cross section. The emergency stop device comprises a bumper switch including first bar 2 formed from an electrically conductive material. The first bar 2 is preferably an elongate flat metal bar having a front face 4 and rear face 6. The first bar 2 defines a metal core, which is surrounded by an electrically insulating layer 8. The electrically insulating layer 8 may be a heat shrink plastic layer, a moulded plastic coating or any other suitable insulting material layer. A series of electrically conductive contacts 10 are arranged along the front face 4 of the first bar 2. The electrical contacts 10 are disc shape elements formed from an electrically conductive material such as copper. The electrical contacts 10 are secured to, and are in electrical contact with the front face 4 of the first bar 2. The electrical contacts 10 project through the insulating coating 8 enabling external electrical contact to be made with the first bar 1. A second bar 12 is formed from an electrically conductive material. The second bar 12 is preferably similar in form to the first bar 2 and comprises an elongate flat metal bar having a front face 14 and rear face 16. The second bar 12 defines a metal core, which is surrounded by an electrically insulating layer 18. The electrically insulating layer 8 may be a heat shrink plastic layer, a moulded plastic coating or any other suitable insulting material layer. The second bar 12 includes a series of electrically conductive rods 20 arranged along the rear face 16. The electrically conductive rods 20 are secured to, and are in electrical contact with the rear face 16 of the second bar 12. The electrically conductive rods 20 project through the insulating coating 18.

The second bar 12 is arranged parallel to the first bar 2 and is spaced forwardly from first bar 2 defining a spacing gap 22. The terms 'front', 'rear', 'forwardly' and 'rearwardly' are relative terms and relate to the arrangement of the components in use, wherein the device is mounted to a mobility scooter having a front and rear, and a forward and rearward direction of travel. A pair of guide rods 24 extend through corresponding apertures 26 in the first bar 2 and the second bar 12, and are arranged at opposing ends of the first bar 2 and second bar 12. The apertures 26 are aligned lengthwise along the bar such that the guide rods are arranged perpendicular to the length of the first bar 2 and second bar 12. The guide rods 24 each comprise a cylindrical metal bar 25 at its core, surrounded by an electrically insulating sleeve 27, which electrically isolates the metal core 25 from the first bar 2 and second bar 12. The second bar 12 is slidingly received on the guide rods 24 such that it is able to slide along the guide rods 24 towards and away from the first bar 1 in a rearward and forward direction transverse to the length of the first bar 2.

The series of electrically conductive rods 20 correspond in number to the series of electrical contacts 10 and are longitudinally aligned with the electrical contacts 10, with each electrically conductive rod 20 being aligned with a corresponding electrical contact. The electrically conductive rods 20 project rearwardly across the gap 22 towards the electrical contacts 10. Each electrically conductive rod 20 has a side wall 28 and a distal end face 30. An electrically insulating sleeve 32 surrounds the side wall 28 of each electrically conductive rod 20. Each sleeve 32 is hollow and open ended, such that a clear passage is defined between each distal end face 30 and the adjacent electrical contact 10. Each sleeve 32 is surrounded by a compression spring 36. The compression springs 36 contact the front face 4 of the first bar 2 at a first end and the rear face 16 of the second bar 12 at a second end. The compression springs 36 are arranged and configured to bias the first bar 2 and second bar 12 away from each other in the forward/rearward direction.

Split pins 38 are provided through the guide rods 24 at opposing ends. The split pins 38 define retaining members that prevent the ends of the guide rods 24 from passing through the apertures 26. Each split pin 38 is located proximate the distal end of the corresponding guide rod 24. The spacing of the split pins 38 along the length of the guide rods 24 sets the maximum spacing of the first bar 2 and the second bar 12. It will be appreciated that any other suitable retaining members may be used, for example circlips, threaded caps or any other retaining member having a diameter greater than the aperture 26.

Each mobility includes charging system for charging the battery of the scooter. The charging system includes a socket for connection to an external power supply. Typically a socket is provided on the steering column or 'tiller' of the scooter that is configured to receive and electrically connect to a plug, such as a 3 pin plug, of a charging plug. The charging system includes an immobiliser/inhibitor that is configured to disconnect the battery to immobilise the motor and prevent the scooter from being driven during charging. This avoids the charging system, and in particular the socket and charger, from being damaged by the charger being forcefully pulled from the socket in the event that the scooter is driven away while the jack plug is in the socket. The immobiliser is activated when a closed electrical circuit is connected to the charging socket. During charging, the closed electrical circuit indicates to the charging system that a power supply has been connected. The immobiliser may function, by way of example, by preventing the supply of power to the electric drive motor. The term immobiliser or inhibitor in the context of the present invention means any system configured to deactivate the electrical drive system, or otherwise stop the vehicle in response to the electrical circuit of the emergency stop device being closed.

The first bar 2 is mounted to the front bumper of a mobility scooter, such that the rear face 6 of the first bar 2 is adjacent the bumper and the front face 14 of the second bar 12 is foremost and forwardly facing. An electrical circuit 40 is connected to the first bar 2 and second bar 12. A first electrical wire 42 is connected to the first bar 2 such that it is in electrical contact with the metal core. The electrical wire 42 is in electrical contact with the electrical contacts 10 via the metal core of the first bar 2. A second electrical wire 44 is connected to the second bar 12 such that it is in electrical contact with the metal core defined by the second bar 12. The electrical wire 44 is in electrical contact with the electrically conductive rods 24 via the metal core of the second bar 12. The first wire 42 and second wire 44 are connected to a jack socket 46, which is connected to by a jack plug 48.

The jack plug 48 is connected to a 3-pin plug 50 that is configured to connect to the charging socket of a mobility scooter. The jack socket 46 is, and the first and second wires.

The springs 36 urge the first bar 2 and second bar 12 apart to the maximum separation, where they are held by the retaining members 38. In this separated configuration, the distal end faces 30 of the electrically conductive rods 20 are spaced from the electrical contacts 10 by a gap 52. The springs 36 are electrically isolated from the second bar 12 by the insulating skin 18 surrounding the bar 12 and the insulating sleeves. The first bar 2 and second bar 12 are therefore electrically isolated from each other and the electrical circuit 40 is broken by the gap 52. When the 3-pin plug is connected to the charging socket of the mobility scooter, and the first and second bars 2,12 are in the spaced configuration, the battery of the mobility scooter remains connected with the scoter in an active state. This is because the immobiliser requires a closed circuit to be connected to the charging socket in order to activate. The user is therefore able to freely drive the scooter when the first and second bars 2,12 are in the spaced configuration. During a front-on collision, the first part of the scooter to come into contact with the object being collided with is the second bar 12 of the emergency stop device. As shown in Figure 2, during the collision an impact force F is applied to the second bar 12, which functions as a bumper plate. The force F causes the second bar 12 to move towards the first bar 2 in a rearward direction. As the second bar 12 moves rearwardly the springs 36 are compressed. The insulating sleeves 32 and 27 are formed from a resilient,

compressible material, and compress as the second bar 12 moves rearwardly. The second bar 12 continues to move rearwardly until it reaches a fully compressed configuration in which the end faces 30 of the electrically conducting rods 20 are in contact with and abut the electrical contacts 10, which prevents further movement of the second bar 12.

Contact between the electrically conducting rods 20 and the electrical contacts 10 completes the electrical circuit 40, which activates the immobiliser o the mobility scooter, causing the battery to disconnect and stopping the motor. Even if the user continues to pull the accelerator lever, the scooter is no longer able to move. The scooter is therefore automatically immobilised immediately upon collision, thereby preventing the further injury or damage that may occur if the scooter were to continue moving or accelerated.

Following the collision, once the force F has been removed, the springs 36 acts to return the second bar 12 to the expanded, separated configuration. The electrical circuit is broken again and the scooter is able to be restarted and operated.

In another embodiment the emergency stop device may include a proximity sensor for detecting the presence of objects within a predetermined distance range ahead of the scooter. The proximity sensor is preferably a contactless sensor. The sensor may comprise a sonic detector such as an ultrasonic distance measuring sensor. The sensor may for example be a non-contact ultrasound sonar for measuring distance to an object.

Alternatively, the sensor may comprise light sensor using light such as laser light or infra red light to measure distance. The sensor may for example comprise a LiDAR sensor such as a Time of Flight LiDAR sensor capable of measuring the distance to an object as close as 10 centimetres. Any other sensor suitable for detecting the presence of an object within an a predetermined safety range may alternatively be utilised.

The sensor is integrated into the electrical circuit of the emergency stop device and the circuit is configured such that a closed circuit is created when the sensor detects an object within a predetermined distance range ahead of the scooter. The system may comprise a controller configured to determine, based on a signal from the sensor, when an objected has entered a predetermined safety range in front of the vehicle, and to cause the circuit to close when such an object is detected. The controller may be configured to receive a signal from the motor and/or a speed sensor or accelerometer on the vehicle indicative of the speed of the vehicle. The controller may be configured to adjust the safety range depending on the speed of the vehicle. In particular, the controller may decrease the safety range in response to an increase in speed and/or increase the range in response to a decrease in speed. The sensor and controller are integrated into the electrical circuit such that, when the circuit is closed in response to an objected within the safety range, the immobiliser is operated to stop the scooter.

The sensor may be provided in addition to or as an alternative to the bumper switch. In one embodiment the emergency stop device includes a proximity sensor and a bumper switch. In an ideal and properly functioning mode of operation the scooter is stopped when an objected is detected by the sensor within the safety range. However, in the event that the scooter is not caused to stop when an object enters the safety range, the bumper switch ensures that the scooter is stopped instantaneously in the event that a collision occurs.

It will be appreciated that the above embodiments describe the use of an emergency stop device to the front of a scooter for detecting objects ahead of the scooter. It will however be appreciated that the emergency stop device could be applied to the rear of a scooter in addition to, or instead of the device located at the front of the vehicle, in all references above to the 'front' of the vehicle and objects 'ahead' of the vehicle are not intended to be limiting to the scope of the invention.