GB2393698A

GB2393698A - Device with stopping distance markings applicable to windscreen

Info

Publication number: GB2393698A
Application number: GB0322526A
Authority: GB
Inventors: Charles Hannant
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-10-04
Filing date: 2003-09-26
Publication date: 2004-04-07
Anticipated expiration: 2023-09-26
Also published as: GB2393698B; GB0223031D0; GB0322526D0

Abstract

An indication device 12, suitable as a vehicle safety device and applicable inside a front windscreen 10, comprises at least one line 22 on a transfer indicating a safe stopping distance between a driven vehicle (50 fig 2) and a vehicle in front (52 fig 2) at a first threshold speed. It may also comprise lateral reference lines 26, 28 and a higher horizontal line 24 corresponding to a safe stopping distance at a higher threshold speed. If the followed vehicle (52) appears below the relevant line 22, 24, this indicates that vehicle separation is insufficient and unsafe. The lines 22, 24 may be formed from red transparent plastic trapped between a clear transparent base sheet and the windscreen 10, the base having an adhesive coating. Before use, the adhesive is protected by a silicone coated cover layer. A method of applying the device 12 includes the drawing of a temporary alignment cross 18 on the windscreen exterior corresponding to a centre of a field of sight of a particular driver.

Description

! 23g3698 5 TITLE: VEHICLE SAFETY DEVICE

10 DESCRIPTION

15 TECHNICAL FIELD

This invention relates to a safety device for measuring the safe stopping distance between road vehicles.

BACKGROUND TO THE INVENTION

The safe stopping distance, i.e. the distance a road 20 vehicle must maintain behind a leading vehicle to stop safely depends on the nature and speed of the vehicle as well as the driving conditions, e.g. road and weather conditions. For a car travelling in normal driving conditions, the stopping distances, which combine both 25 personal reaction or thinking distance and braking distance, set out in the Highway Code are 12m at 20mph, 23m at 3Omph, 36m at 4Omph etc. up to 96m at 7Omph. However, it is difficult for a driver to judge whether he is

maintaining a safe distance between his vehicle and the leading vehicle.

One solution is to mark chevrons on the road surface and advise a driver how many chevrons he should maintain 5 between his vehicle and a leading vehicle at a particular speed. However, it is impractical to provide chevrons on all roads. Another solution is to fit each road vehicle with a radar sensor, but this solution is very expensive.

Alternative solutions in the form of devices to be 10 mounted to a vehicle windscreen are provided in US patents 3,859,732 and 4,417,404. Both devices comprise transparent plates having a plurality of spaced apart reference lines marked with indicia showing the separation and the maximum safe speed for that separation. The driver views a leading 15 vehicle through the device and determines the distance to the leading vehicle by comparing the height of its bumper with the reference lines. Since there are multiple reference lines and indicia, the devices may confuse a driver and, by their construction, may impede the driver's 20 line of sight.

It is an object of the present invention to provide a simplified device for indicating safe stopping distances for road vehicles.

DISCLOSURE OF THE INVENTION

25 The present invention provides a vehicle safety device for indicating to a driver the safe separation to be maintained between a first vehicle to which the device is mounted and which is driven by the driver and a leading

vehicle, the device comprising at least one distance reference line for alignment with a second vehicle and representing a safe stopping distance and means for fixing the at least one distance reference line to a windscreen of 5 the first vehicle, characterized in that the device is in the form of a transfer whereby the at least one distance reference line is transferable to the windscreen of the first vehicle.

The device may comprise a first distance reference 10 line representing the safe stopping distance at a first I threshold speed and a second distance reference line representing the safe stopping distance at a second threshold speed which is higher than the first threshold speed. The first threshold value may be the normal speed 15 when driving in urban areas, e.g. 30mph. The second threshold value may be the maximum speed when driving along unrestricted dual carriageway open roads in the U.K., e.g. 70mph. Thus the device may consist of two distance reference lines.

20 By using only two lines and representing the two most common driving speeds, there is no need for indicia to indicate the value of the lines, although such indicia may be provided if desired. Moreover, by using a transfer, only the lines need be mounted on the windscreen. There is 25 no essential need for a separate member which supports the lines to be attached to the windscreen. Thus, the risk of the device obstructing the driver's line of sight is reduced. If desired however, the transfer may comprise a

flexible member supporting the distance reference lines and in the form of a transparent sheet, e.g. of plastics, may be adhered on the windscreen. The lines may be printed on the sheet.

5 The first and second reference lines may be generally parallel and may be generally horizontal when the device is mounted to the windscreen. The lines may be curved to compensate for the curvature of the windscreen. The degree of curvature may be adjusted for each vehicle. The lines 10 may be of plastics film, which may be coloured, e.g. red.

When the first vehicle is travailing at the first threshold speed, a safe distance is maintained between vehicles when the leading vehicle appears above the first reference line. Similarly at the second threshold speed, a 15 safe distance is maintained when the vehicle is above the second reference line. The device is thus simple to use.

The device may comprise at least one lateral reference line which assists a driver to determine the lateral placement of the vehicle, e.g. in a lane of a multi-lane 20 carriageway. The lateral reference lines are transferable to the windscreen in a similar manner to the distance reference lines, and preferably simultaneously therewith.

When mounted on the windscreen, the lateral reference line aligns with a road marking defining one side of the lane.

25 The device preferably comprises two such lateral reference lines, one to be aligned with each side of the lane. For example, where the lane is defined by left and right hand lines, the device may have left and right lines which in

use align with the left hand and right hand lines of the lane. The right and left lateral reference lines will be converging and may intersect the distance reference lines.

The safe stopping distance and the lateral reference 5 lines are designed so that the line of sight of the driver is not interrupted. The lines may be fine solid lines.

Alternatively, and especially if the lines are thicker, they may be translucent or transparent.

The transfer may comprise a base layer having an 10 adhesive coated surface on which the distance reference and/or lateral reference lines are temporarily and peelably mounted in fixed relationship. A cover layer having a silicone or other release-coated face may be temporarily and peelably adhered to the base layer by the adhesive 15 layer on the base layer to cover the reference lines. The device may be mounted to a windscreen by peeling off the cover layer from the backing layer to expose the reference lines and applying the adhesive coated side of the base layer to the windscreen. The base layer may then be peeled 20 away from the windscreen to leave the reference lines attached to the windscreen. The adhesive layer is designed so that the adhesive remains attached to the base layer when the base layer is removed from the windscreen.

The invention is diagrammatically illustrated, by way 25 of example, in the accompanying drawings, in which:-

BRIEF DESCRIPTION OF THE DRAWINGS

Figure la is an interior forward-facing view of a motor vehicle to which a safety device according to the

present invention has been mounted; Figure lb is an enlarged view through the windscreen of the motor vehicle of Figure la and showing the safety device mounted to the windscreen, and 5 Figure 2 is a side view of the motor vehicle of Figure la and a leading vehicle.

DETAILED DESCRIPTION OF THE DRAWINGS

In Figures la and lb there is shown a vehicle windscreen 10 on the interior of which a safety device 12 10 is mounted using the method described below. The safety device 12 is mounted on the driver's side of the windscreen above the steering wheel 14 so that the driver has an unimpeded view of the device 12 when facing forwards.

In Figure 2 there is shown the vehicle 50 which is to 15 receive the safety device 12 and a leading vehicle 52. The straight dotted line 16 represents the line of vision or sight of a driver of the first vehicle 50 through the safety device to a position where the rear wheels of the leading or second vehicle 52 appear to meet the road.

20 Figure lb is an enlarged view through the windscreen of the vehicle 50 and showing the safety devices 12 after the device has been mounted to the windscreen 10. The device comprises a pair of generally straight parallel, generally horizontal distance reference lines 22,24.

25 Alternatively the distance reference lines may be curved to compensate for the curvature of the windscreen. The lines are mounted direct to the windscreen and are thin enough so as not to obstruct or interfere with the driver's vision.

The pairs of lines are guides for determining the safe stopping distance. The lower line 22 of the pair of lines is positioned on the windscreen to show the safe stopping distance when driving at a first threshold value speed, say 5 30mph. A leading vehicle 52 visible through the device should appear above the lower line 22. Similarly the upper line 24 of each pair of lines is positioned on the windscreen to show the safe stopping distance when driving at a second threshold value speed, say 70mph. Thus, if the 10 vehicle S2 ahead appears below the respective distance reference line, the driver is driving too close to that vehicle. The device also comprises a pair of lateral reference lines 26,28. The lines are straight, dashed, and upwardly 15 converging and are guides for the lateral positioning a vehicle in a road lane. For example, when driving in a lane the width of which is defined by left and right-hand road markings, which are often in the form of white lines painted on the road surface, the device is positioned on 20 the windscreen so that the left line 26 and the right line 28 align with the left hand and right hand lines of road markings defining the lane.

The safety device 12 is in the form of a transfer of generally conventional construction comprising a base layer 25 or sheet having an adhesive coated upper surface on which the distance reference and lateral reference lines are supported. The lines are formed from flexible plastics film which is preferably coloured, e.g. red, and which is

preferably transparent. A cover layer or sheet temporarily covers the adhesive coating on the base layer and traps the reference lines therebetween and is held to the base layer by the adhesive coating. Normally the cover layer will be 5 coated with a release agent, such as silicone, to assist its subsequent removal.

The method for mounting the safety device to the windscreen 10 of a vehicle 50 is as follows, namely: a) Park the vehicle 50 at the safe stopping distance of the 10 threshold speed represented by the lower line behind a stationary vehicle 52, for example, at a distance of 23 metres where the bottom distance reference line is set to a threshold value of 30mph. This is shown in Figure 2; 15 b) With the aid of a helper, mark a horizontal line on the external surface of the windscreen 10, e.g. with a felt-

tip pen, on the driver's line of sight and in a position indicating where the wheels of the stationery vehicle 52 meet the road when the driver is positioned in his/her 20 normal driving position. Then form a cross 18 by marking a vertical line on the external surface of the windscreen crossing the horizontal line to indicate the centre of the driver's field of sight. These steps are

preferably done by or with the cooperation of the driver 25 of the vehicle 50 since each driver may have a different driving position and height, and c) Affix the device to the inside face of the windscreen with the bottom distance reference line of the device

aligned with the marked horizontal line and horizontally and with the vertical marked line centrally between the lateral lane marking lines.

Step (c) is achieved by removing the cover layer from 5 the transfer to expose the adhesive layer. The backing layer is then temporarily fixed, by means of the exposed adhesive surface, to the windscreen, preferably on the interior face thereof. The base layer 46 is then peeled off the windscreen to leave the distance and lateral reference 10 lines bonded to the windscreen. The adhesive layer is removed with the base layer to leave only the lines fixed to the windscreen.

The transfer is arranged such that the two distance reference lines are in a fixed relationship such that it is 15 not necessary to repeat the windscreen marking and aligning step for the higher speed distance reference line 24. In addition the transfer is arranged so that the lateral lane marking lines are in fixed relation to the distance reference lines so that a single mark on the windscreen 20 when positioned centrally in the driver's line of sight is enough to determine the correct positioning of both the distance reference and line marking lines of the transfer.

The invention thus provides a simple and inexpensive safety device for a road vehicle and which overcomes the 25 disadvantages of the prior art devices.

Claims

! CLAIMS

1. A vehicle safety device for indicating to the driver of a first road vehicle the safe separation to be maintained between the first vehicle to which the device is 5 mounted and a leading road vehicle, the device comprising at least one distance reference line representing a safe stopping distance and means for fixing the at least one distance reference line to a windscreen of the first vehicle, characterized in that the device is in the form of 10 a transfer whereby the at least one distance reference line is transferable to the windscreen of the first vehicle.

2. A vehicle safety device according to claim 1, wherein the transfer comprises two distance reference lines, a first distance reference line representing the safe 15 stopping distance at a first threshold speed and a second distance reference line representing the safe stopping distance at a second threshold speed which is higher than the first threshold speed.

3. A vehicle safety device according to claim 2, wherein 20 the first threshold value is the normal speed when driving in urban areas.

4. A vehicle safety device according to claim 2 or claim 3, wherein the second threshold value is the maximum speed when driving along dual carriageway roads.

25

5. A vehicle safety device according to any one of claims 2 to 4, wherein the distance reference lines are generally parallel and generally horizontal.

6. A vehicle safety device according to any preceding

claim, wherein the at least one distance reference line is curved to compensate for the curvature of the windscreen.

7. A vehicle safety device according to any preceding claim, wherein the at least one distance reference line is 5 transparent.

8. A vehicle safety device according to any preceding claim, wherein the transfer comprises at least one lateral reference line which is transferable to the windscreen to assist the driver to determine the lateral placement of the 10 first vehicle in a road lane.

9. A vehicle safety device according to claim 8, wherein the transfer comprises two such lateral reference lines, one to be aligned with each side of the road lane.

10. A vehicle safety device according to any preceding 15 claim when dependent on claim 2, wherein the transfer has two distance reference lines mounted on a common backing sheet for application together to the vehicle windscreen in a fixed relationship.

11. A vehicle safety device according to claim 10 when 20 dependent on claim 9, wherein the two lateral reference lines are arranged in fixed relationship with themselves and with the distance reference lines on the backing sheet.

12. A vehicle safety device according to any preceding claim, wherein the transfer comprises a base layer having a 25 surface to which the or each distance reference line is peelably mounted, and a cover layer peelably mounted to the base layer to cover the reference lines.

13. A road vehicle having a windscreen and having a safety device according to any preceding claim mounted on the windscreen.

13. A vehicle safety device substantially as hereinbefore

t described with reference to and as illustrated in the accompanying drawings.

14. A road vehicle having a windscreen and having a safety device according to any preceding claim mounted on the 5 windscreen.

Amendments to the claims have been filed as follows 1. A vehicle safety device for indicating to the driver of a first road vehicle the safe separation to be maintained between the first vehicle to which the device is 5 mounted and a leading road vehicle, the device comprising at least one distance reference line representing a safe stopping distance and means for fixing the at least one distance reference line to a windscreen of the first vehicle, characterized in that the at least one distance 10 reference line is transparent and in that the device is in the form of a transfer whereby the at least one transparent distance reference line is transferable to the windscreen of the first vehicle.

2. A vehicle safety device according to claim 1, wherein 15 the transfer comprises two distance reference lines, a first distance reference line representing the safe stopping distance at a first threshold speed and a second distance reference line representing the safe stopping distance at a second threshold speed which is higher than 20 the first threshold speed.

3. A vehicle safety device according to claim 2, wherein the first threshold value is the normal speed when driving in urban areas.

4. A vehicle safety device according to claim 2 or claim 25 3, wherein the second threshold value is the maximum speed when driving along dual carriageway roads.

5. A vehicle safety device according to any one of claims 2 to 4, wherein the distance reference lines are generally

parallel and generally horizontal.

6. A vehicle safety device according to any preceding claim, wherein the at least one distance reference line is curved to compensate for the curvature of the windscreen.

5 7. A vehicle safety device according to any preceding claim, wherein the transfer comprises at least one lateral reference line which is transferable to the windscreen to assist the driver to determine the lateral placement of the first vehicle in a road lane.

10 8. A vehicle safety device according to claim 7, wherein the transfer comprises two such lateral reference lines, one to be aligned with each side of the road lane.

9. A vehicle safety device according to any preceding claim when dependent on claim 2, wherein the transfer has 15 two distance reference lines mounted on a common backing sheet for application together to the vehicle windscreen in a fixed relationship.

10. A vehicle safety device according to claim 9 when dependent on claim 8, wherein the two lateral reference 20 lines are arranged in fixed relationship with themselves and with the distance reference lines on the backing sheet.

11. A vehicle safety device according to any preceding claim, wherein the transfer comprises a base layer having a surface to which the or each distance reference line is 25 peelably mounted, and a cover layer peelably mounted to the base layer to cover the reference lines.

12. A vehicle safety device substantially as hereinbefore described with reference to and as illustrated in the

( accompanying drawings.