GB2270587A

GB2270587A - Message display for vehicles

Info

Publication number: GB2270587A
Application number: GB9312237A
Authority: GB
Inventors: William Alexander Courtney
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-09-10
Filing date: 1993-06-14
Publication date: 1994-03-16
Anticipated expiration: 2013-06-14
Also published as: GB9312237D0; GB2270587B

Abstract

This invention relates to devices for displaying visual information at the rear of a vehicle. It also acts as a parking aid when reversing the vehicle. A common problem experienced by vehicle drivers is that of other road users travelling too close to their own vehicles, particularly when travelling at speed. This driving style is liable to cause accidents and also causes stress for the driver in the front vehicle. The invention described is an illuminated display, mounted at the rear of a vehicle. The display housing forms part of a vehicle spoiler or airfoil, this reduces the air resistance of the display and offers vehicle performance and styling benefits. The display carries a warning message alerting other drivers of their closeness. In order to enhance the readers perception of the message it may be switched on and off at intervals. The message board is changeable, allowing the message to be altered according to circumstances. For example this allows the message to be displayed in different languages. The electrical operating system can be controlled by a switch on the dash board. Operation may be continuous or short term while a pressure sensitive switch is depressed. The message board may be programmable, allowing the message to be changed by the driver operating a key pad inside the vehicle. A range of variable display elements are possible, including light emitting diodes and back lit liquid crystals. The spoiler and display system can also be gainfully integrated with a light bending optical system in order to reduce the size of the blind spot, at the rear of the vehicle created by the display and also allow the driver to look into the region normally obscured from view by the presence of the rear bodywork of the vehicle. In this system, ray (4) from internally lit message display (3) are refracted by Fresnel prism (2) and travel horizontally rearward from the vehicle. Rays (5, 6) from the blind-spot region are also refracted by prism (4) and travel to interior mirror, to improve rearward visibility when reversing. The system may be used in conjunction with a distance sensor, e.g. in parking, in which instance, an audible warning may also be activated. <IMAGE>

Description

Dynamic Message Display for Vehicles This invention relates to devices for displaying visual information at the rear of a vehicle.

It also acts as a parking aid when reversing the vehicle.

A common problem experienced by vehicle drivers is that of other road users travelling too close to their own vehicles, particularly when travelling at speed. This driving style is liable to cause accidents and also causes stress for the driver in the front vehicle.

The invention described is an illuminated display, mounted at the rear of a vehicle.

The display housing forms part of a vehicle spoiler or airfoil, this reduces the air resistance of the display and offers vehicle performance and styling benefits. The display carries a warning message alerting other drivers of their closeness. In order to enhance the readers perception of the message it may be switched on and off at intervals. The message board is changeable, allowing the message to be altered according to circumstances. For example this allows the message to be displayed in different languages. The electrical operating system can be controlled by a switch on the dash boared. Operation may be continuous or short term while a pressure sensitive switch is depressed.

The message board may be pTogrammable, allowing the message to be changed by the driver operating a key pad inside the vehicle. A range of variable display elements are possible, including light emitting diodes and back lit liquid crystals.

The spoiler and display system can also be painfully integrated with a light bending optical system in order to reduce the size of the blind spot, at the rear of the vehicle created by the display and also allow the driver to look into the region normally obscured from view by the presence of the rear bodywork of the vehicle.

The invention will be illuminated by reference to specific exzunples.

Figure 1 shows a cross section of a housing which includes a message board as a window.

The housing is shaped to form an integral part of an air spoiler or airfoil which is contoured to offer aerodynamic benefits. The diagrams in this application illustrate a basic indicative aerodynamic shape.

Those with a knowledge of vehicle aerodynamics wiU be able to tailor the shape of the housing for specific aerodynamic purposes.

The housing, 1 encloses a lamp or battery of lamps, 2. 3 is a reflecting surface which assists in directing light towards the translucent message board, 4. The device is mounted at the rear of the vehicle and occupies a substantial proportion of the width of the rear of the vehicle. In the case of a saloon vehicle it can be mounted on top of the boot. Adjustable brackets can be added to allow the device to be mounted on the rear window struts of hatchback and estate vehicles. The message board can be inserted in grooves in the body of the housing and secured using screws, clips or other mechanical bonding hardware. The board is replaceable allowing different messages to be displayed. 5 is an alternative message board stored for future use.

A range of wiring arrangements are available to suit different market demands. The circuit can be activated by means of a standard on-off switch mounted on or near the dashboard or a pressre sensitive switch which only activates the circuit for the duration of depression of the switch. Audio and/or visual warnings may be emitted inside the cabin when the display is in operation. The circuit may also be wired to act in harmony with the normal brake lights. One or more flipflop switches similar to those used for indicator lights can be included to switch the lamp or laws on and off at regular, frequent intervals. In the case of a multiple lamp system the flipflops may be connected in order to illuminate different words on the display board in sequence.

Figure 2 shows a typical message board. The rigid board may be replaced by a flexible message board allowing a number of messages to be spooled for future use. The spool may be rotated mechanically or remotely from inside the vehicle.

Figure 3a shows a message board which depresses a micro switch, 1 which connects the source of illumination for the display board in parallel with the brake light circuit. As a consequence the display board is illuminated when the brake pedal is depressed. A similar arrangement may be used to connect the source of illumination for the board to the wiring circuit for the hazard warning lights.

Figure 3b shows a different message board which fails to close the micro switch, 2 so that operation of the display board illumination and the operation of the brake lights are not related.

A disadvantage of mounting any rear spoiler within the rear line of sight of the vehicle driver is that it obscures the rear view. This is of particular disadvantage when reversing the vehicle. This may be overcome in the present invention by mounting a prism or lens on top of the housing so that it deviates light from the blind spot, behind the vehicle towards the drivers rear view mirror. In order to reduce the bulk of this optical arrangement the lens or prism should be of the Fresnel type. Figure 4 shows a typical arrangement. 1 in the figure is a Fresnel purism.

Figure 5 shows a more elegant variation of the light bending spoiler version of the device. One or more lamps(1,2,3 and 4 in figure 4) are mounted in the base of the device. 5 is the message board and 6 is a Fresnel prism. 7 is an optional transient sheet to protect the prism and message board from the weather and ingress of dirt. Light from the message board is totally internally reflected by the prism allowing the message to be seen by a driver travelling behind the vehicle. The presentation of the message on the board is orientated to allow for inversion by the prisms.

Figure 6 shows one segment, 1 of the Fresnel prism for this arrangement. 2 is a reflected ray of light which is travelling from the message board to the rear of the vehicle. Rays similar to 1 are seen by drivers close to the rear of the vehicle. 3 is a ray of light travelling from the blind spot behind the vehicle towards the vehicle drivers mirror.

In order to increase the field of view of the optical system when reversing the peripheral prism elements of the optical system may be be configured to act in a similar manner to diverging lenses.

Figure 7 shows a variation on the innovation which allows the height of the displayed message to exceed the height of the spoiler as seen by the driver when looking to the rear of his 'her vehicle.

A second advantage of this variation is that compared with the designs described above it offers a larger field of vision for the driver when looking back into the blind spot.

Figure 7 illustrates the essential optical principles relating to the innovation. The detailed design features are variables which may be chosen by those with a knowledge of vehicle design, in order to harmonise with the design of the rest of the vehicle. 1 is part of the rear bodywork of the vehicle, for example the boot lid. 2 is a vertical orwIearverticalFresnel prism. 3 is the message board., assumed for this example to be a flat internally lit display. 4 is an example of a ray of light emitted by the display board which travels towards the Fresnel prism and is then deviated so that it merges from the prism along an approximately horizontal path.The lines with arrow heads drawn parallel to 4 represent other light rays deviated in a similar manner. 5 and 6 are light rays which travel from locations inside the blind spot at the rear of the vehicle and are then deviated by the Fresnel prism so that they travel towards the interior rear view mirror. 7 is a sheet of transparent material which forms part of the leading face of the air spoiler. In the example shown 7 is a parallel sided sheet. It may however include a second Fresnel prism in order to increase the deviation of the light rays travelling from the blind spot, enabling the driver to look into the blind region closer to the back of the vehicle.

The surface shape and rake angle of 7 are a design variable which can be chosen in order to optimize aerodynamic performance.

In order to reduce the problems caused by deposition of road dirt during wet weather the exterior optical surfaces may be treated with a chemical coating which reduces the adhesion between road dirt and the optical SurfilceL Industrial chemists are aware of the chemicals required to fulfii this duty.

Cleansing of the exterior optical surfaces may also be accomplished using washer and wiper systems as used on car windscreens and head laws.

An alternative method of reducing the deposition of road dirt is to lower the point at which the air streamlines flowing over the upper part of the vehicle break away from the bodywork at the rear of the vehicle. This can be assisted by adding an airfoil above the light bending rear spoiler Figure 8 shows a cross section of such an arrangement. The airfoil, 1 is mounted above the light bending spoiler, 2. This aerofoil also acts as a cowling, reducing the amount of scattered light reflected towards the drivers eye when carrying out the reversing manoeuvre and acting as a frarnework to isolate the rear drivers vision of the display board.

The upper airfoil or cowling may include optical elements, so that when the surfaces are fairly clean they also assist in the reversing manoeuvre. It may also include a source of illumination which becomes operational under specific circumstances, for example when reversing or braking.

If a large display is required the air spoiler message board may be combined with a vertically mounted display board located at the rear of the vehicle, below the spoiler such that a viewer to the rear of the vehicle registers the two message boards as one visual unit.

In any of the above versions of the invention the message board and lamps may be replaced by a matrix of light emitting diodes. (lets), lightemitting plastic or other electronically, remotely controlled message elements such as a back lit liquid crystal display.The on-off pattern of the LEDs or other message elements may be controlled by an electronic unit which can be programmed to store a nuneber of different messages. For example to warn of an accident or to display warnings in different languages.

Figure 9 shows a suitable control pad inside the vehicle.

1 is a scrolling switch which is pressed to alter the message selected. 2 is a second scrolling switch which is used to select the language in which the message on the rear spoiler is is displayed. Those with a knowledge of electronic engineering will be able to construct a suitable display board and associated key pad which will perform as described in this patent application.

The display may be designed to operate automatically if other vehicles are in the proximity. The proximity sensors may be electromagnetic or ultrasonic based. The sensors could allow for different vehicle speeds and weather conditions. Those with a knowledge of electronic sensors would be capable of designing such a sensor using existing technology.

The distance sensing system may also be used to advantage when parking. In this mode of operation the display is switched on and an optional sound is emitted if the rear of the vehicle carrying the system becomes in close proximity to another vehicle. The display board may also display a "Danger Reversing" message. In addition to warning pedestrians of the manoeuvre this display will provide extra illumination to the rear of the vehicle.

An advantage of the present system over existing systems which emit an audible sound when vehicles are in close proximity is that the driver can park hisiller vehicle with the system left in sleeping mode.

In this mode the display automatically displays a "Keep your distance" message if other drivers move close to the vehicle when carrying out parking manoeuvres. This will reduce the likelihood of other vehicles damaging or blocking in the vehicle carrying the display systems In order to prevent undue loss of energy from the car battery the display switches itself off after a short time interval.

When the vehicle driver is using the light bending spoiler as an aid for reversing the vehicle a problem commonly encountered is that of trying to reverse the vehicle into a space of restricted width, This manoeuvre requires centralising the rear of the vehicle between two obstacles. This task is made easier if in addition to the seeing into the blind spot the driver is also able to gauge the central point between the obstacles.

Figure 10 shows a mirror unit which assists in making this judgement. The unit consists of two mirrors, 1 and 2. These are mounted above or close to the standard interior rear view mirror. They are angled in order to deviate light travelling from behind the two extreme rear edges of the vehicle to the drivers eyes. Provided that the width of these mirrors exceeds the distance between the drivers eyes the two images will appear to be supsiwd.

Figure 11 shows a mirror unit which performs the same operation but which is advantageously made up of a multiplicity of pairs of mirrors.

Claims

1. An illuminated written message display which is incorporated into an aerodynamically shaped rear air spoiler or airfoil.

2. As for claim 1 but with an interchangeable message display board.

3. As for the above claims for a display which includes an onff switch that emits a visible or audio signal to alert the operator that the system is in operation.

4. As for any of the above claims for a display which incorporates a flip flop switch which causes intermittent illumination of the message board.

5. As for any of the above claims for a display which is segmented so that different portions of the display are illuminated at different points in time.

6. As for any of the above claims for a display which is electrically connected to the brake light system so that all or part of the display board is illuminated when the brakes are applied.

7. As for any of the above claims for a display which is electrically connected to the hazard light system so that all orpart of the display board is illuminated when the hazard lights are switched on.

8. As for any of the above claims for a display which is built into a housing which includes an optical system which deviates light, allowing the driver to look into the blind spot behind the vehicle when reversing.

9. As for any of the above claims for a display which includes a message board which is mounted approximately horizontally and is viewed by drivers to the rear of the vehicle after the light from the board has been deviated by an optical system or suffered total internal reflection by a prism system.

10. As for the above claim, but in which the angle and position of the prism is such that the prism also deviates light from the blind spot at the rear of the vehicle towards the interior rear view mirror.

11. As for any of the above claims for an optical system which is incorporates Fresnel prisms or lenses.

12. As for any of the above claims for a display which consists of light emitting diodes, light emitting plastic elements or other small sources of light which are arranged in a matrix so that an electronic control system can be progranuned to allow different messages to be displayed.

13. As for any of the above claims for a display which consists of light absorbing display elements which can be remotely switched to light absoing or light transparent mode and which are made conspicuously visible by back lighting.

14. As for any of the above claims for a display which includes a cowling to reduce the amount of unwanted scattered light falling on the display or other extemal optical surfaces.

15. As for the above claim for a cowling which also acts as an aerofoil, deflecting dirt laden air away from the extemal optical surfaces of the display.

16. As for any of the above claims for a display which includes a cowling or airfoil which also includes light deviating optical elements.

17. As for any of the above claims for a display system which integrates a spoiler mounted display board with a vertically or near vertically mounted display board in order to display an integrated message.

18. As for any of the above claims for a display which includes chemically treated surfaces which discourage adhesion of dirt to exposed surfaces.

19. As for any of the above claims for a display which includes a washer and/or wiper device to clean a viewed surface of the display.

20. As for any of the above claims for a display which incorporates adjustable brackets which allow the device to be mounted on a range of surfaces which are at different angles to the vertical.

21. As for the above claim for a display for which the angle to the vertical can be remotely altered by the driver sitting in the driving seat.

22. As for any of the above claims for a display for which the angle to the vertical changes when the reverse gear of the vehicle is engaged.

23. As for any of the above claims for a display for which the angle to the vertical changes in response to a change of road speeds

24. As for any of the above claims for a display which is triggered by a signal from an electromagnetic or ultrasonic sensing system which detects the proximity of other vehicles.

25. As for the above claim, but in which the triggering distance of the other vehicle is a function of vehicle speed

26. As for any of the above claim, but for a system which can allow a compensation factor for different road or weather conditions.

27. As for the system in any of the above claims but including a mirror unit mounted in the proximity of the internal driving mirror which also allows the centre of gaps to the rear of the vehicle to be judged when reversing the vehicle.

28. As for the system in any of the above claims but which continues to operate even when the ignition circuit is switched off such that it displays an indicative message if other vehicles move within close proximity of the vehicle.

29. As for the system in any of the above claims but which includes an electronic or mechanical translotor which enables a message selected by a driver in a preferred language to be displayed in a different language.