GB2118753A

GB2118753A - A safety system for a vehicle

Info

Publication number: GB2118753A
Application number: GB08208514A
Authority: GB
Inventors: James Steel
Original assignee: Ogden Electronics Ltd
Current assignee: Ogden Electronics Ltd
Priority date: 1982-03-23
Filing date: 1982-03-23
Publication date: 1983-11-02

Abstract

A safety system for a vehicle comprises an inflated flexible tubular fender (15) extending transversely of a rear surface (10) of the vehicle and containing a pressure sensitive device (16) connected to a circuit (23) for operating a valve (29) of a brake system of the vehicle. If, while reversing, the fender (15) engages an object and a wall of the fender is flexed inwardly by the object causing increase of pressure of air in the fender, the brakes of the vehicle are automatically applied. A gear selector switch is in series with a switch associated with the pressure sensor so that brake control and an alarm signal is only provided during reversing. In addition, the fender is normally in a collapsed and coiled state and in response to reverse gear selection a pump 17 is operated to inflate the fender. <IMAGE>

Description

SPECIFICATION A safety system for a vehicle This invention relates to a safety system for a vehicle and, more particularly, to apparatus for effecting operation of retarding means of a vehicle.

It is known to provide apparatus for automatically effecting operation of retarding means of a vehicle when the vehicle is reversing and encounters an object in the path of movement of the vehicle. Such apparatus generally includes a radar scanner for detecting an object in the path of the vehicle. While such safety systems may be acceptable for some applications, for other applications they may be expensive.

It is desirable, therefore, to provide a safety system for a vehicle which is less expensive than hitherto without impairing the effectiveness of the system.

According to the present invention there is provided apparatus for effecting operation of retarding means of a vehicle comprising a fender engageable by an object in the path of the vehicle, a sensor for sensing displacement of at least a portion of the fender, a first electrical switch operable by a motion selector of the vehicle, a second electrical switch operable to effect operation of the retarding means, and an electrical circuit including an electric power source, the sensor, the first switch and the second switch and arranged such that, when the sensor senses displacement of the fender when engaged by the object after the selector has been moved to select direction of movement of the vehicle in the said path, the second switch operates to effect operation of the retarding means thereby retarding movement of the vehicle in the said direction.

The retarding means of the vehicle therefore is automatically operated if, during movement of the vehicle in the said path, the fender engages an object in the path.

The fender may comprise an inflatable flexible member containing gas and the sensor is adapted to sense change of pressure of the gas.

If, therefore, the fender engages an object in the path of the vehicle, a wall of the fender is compressed by the object with a result that there is a change of pressure of the gas contained within the flexible member which change of pressure is sensed by the sensor.

The inflatable member may be carried by support means.

The support means may be adapted to move the inflatable member from a first location adjacent a surface of the vehicle to a second location spaced from the said surface.

The flexible member may be elongate and the support means may comprise a pair of support members which, when the inflatable member is at the second location, are elongate and extend substantially orthogonal to a longitudinal axis of the inflatable member.

The support members may support opposite end portions of the flexible member.

Each support member may comprise a flexible tubular member having an elongate resilient strip extending longitudinally thereof, each strip causing each corresponding tubular member to coil upon itself when the flexible member returns from the second location to the first location.

Each said tubular member may be connected to means for supplying gas to the tubular members.

The circuit may include a third electrical switch for effecting operation of means for supplying gas under pressure from the supply means to the tubular members when the selector is moved to select the predetermined direction of motion of the vehicle.

Following is a description, by way of example only and with reference to the accompanying drawing which is a diagrammatic representation, of one method of carrying the invention into effect.

Referring to the drawing, there is shown a rear surface of a vehicle, such as a bus, diagrammatically represented by the line 10. The rear surface has secured thereto opposite end portions of a pair of spaced parallel inflatable tubular members 11, 12 each containing an elongate metallic strip extending longitudinally of each corresponding tubular member 11, 12 and being coiled so that each tubular member 11, 12 in a deflated condition is coiled, as shown at A in the drawing. When inflated, the longitudinal axes of the tubular members 11, 12 extend orthogonal to the rear surface 10 of the vehicle.The end portions of the tubular members 11, 12 remote from the rear surface 10 of the vehicle are attached to an outer surface at corresponding end portions of an elongate fender 1 5 comprising an inflated tubular member of flexible material which is sealed at opposite ends. The fender 1 5 contains air which is maintained at a predetermined pressure, for example 80 psi, and has extending longitudinally thereof an electrical pressure sensitive device 1 6 adapted to generate signals in an electric circuit including the device 1 6 when air pressure in the fender 15 deviates from the predetermined pressure. The pressure of air in the fender is maintained by means of a pump 17 connected to the fender 1 5 by means of a conduit 18.

The tubular members 11, 12 are each provided with a pressure sensitive device 19, 20 extending into end portions of the corresponding tubular members 11, 12 adjacent the rear surface 10 of the vehicle. The tubular members 11, 12 are supplied by air from the pump 17 through a conduit 21, the pump being controlled to supply air to the tubular members 11 and 12 by means of a control device 22 whereby air is supplied to the tubular members 11 and 12 to inflate and thereby uncoil the members 11, 12 against the resilient bias of the coil springs 13, 14 from the position shown at A in the drawing to the position in which the tubular members 11, 12 are shown in full lines in the drawing and to cut off supply of air to the tubular members 11, 12 whereby the air contained in the tubular members drains to atmosphere through the conduit 21 and the pump 17 with a result that the tubular members are coiled due to the resilient bias of the coil springs 13,14.

The pressure sensitive devices 1 6, 1 9 and 20 are connected in an electric control circuit 23 which also includes a visual indicating device 24 and an audible indicating device 25. Supply of electric power to the control circuit 23 is from a battery 26 and is controlled by a switch 27 operated by a gear selector 28 of the vehicle. The switch 27 is arranged such that power is supplied from the battery 26 to the circuit 23 and from the battery 26 to the control device 22 of the pump 1 7 when the gear selector 28 is moved to select reverse gear of the vehicle. The control circuit 23 also is connected to a valve 29 for supplying fluid in a brake system of the vehicle whereby, when the valve 29 is actuated, the brakes of the vehicle are operated.

During normal operation of the vehicle, the fender 1 5 is located in a retracted position adjacent the rear surface 10 of the vehicle, the tubular members 11, 12 being deflated and thereby being coiled due to the resilient bias of the coil springs 13, 14. When reverse gear of the vehicle is selected by moving the gear selector 28 to a position to select reverse gear, the control circuit 23 and the control device 22 of the pump 1 7 are connected to the battery 26 by the switch 27.The control device 22 controls the pump 17 such that air is supplied to the tubular members 11, 12 from the pump 17 through the conduit 21 thereby inflating and uncoiling the tubular members 11, 12 2 against the resilient bias of the coil springs 13, 14. In consequence, the fender 1 5 is moved from a retracted position to a displaced position, as shown in full lines in the drawing, spaced rearwardly from the rear surface 10 of the vehicle.

If, during reversal of the vehicle, any or all, or any combination of the tubular member 11 , the tubular member 12 and the fender 1 5 engage an object, pressure of air in the corresponding tubular member 11, or 12 or the fender 15 is increased due to the wall of the corresponding tubular member 11 or 12 or the fender 1 5 being flexed inwardly on contact with the object. In consequence, the corresponding pressure sensitive device 1 6, 1 9 or 20 generates a signal in the circuit 23 with a result that signals are transmitted to the visual indicating device 24, the audible indicating device 25 and the valve 29 of the brake system of the vehicle. In consequence, a visual and audible indication that the vehicle has engaged an object is provided and the brake system of the vehicle is actuated automatically thereby arresting further rearward movement of the vehicle.

The visual and audible indicating devices 24, 25 and the valve 29 of the brake system are deactivated if the gear selector 28 is moved from a position selecting reverse gear since supply to the circuit 23 from the battery 26 would then be cut off by movement of the switch 27. The devices 24 and 25 and the valve 29 also would be deactivated if the object were to be removed from contact with the fender 1 5 and/or either or both of the tubular members 11,12.

Claims

1. Apparatus for effecting operation of retarding means of a vehicle comprising.

a fender engageable by an object in a path of the vehicle, a sensor for sensing displacement of at least a portion of the fender, a first electrical switch operable by a motion selector of the vehicle, a second electrical switch operable to effect operation of the retarding means, and an electrical circuit including an electric power source, the sensor, the first switch and the second switch and arranged such that, when the sensor senses displacement of the fender when engaged by the object after the selector has been moved to select direction of motion of the vehicle in the said path, the second switch operates to effect operation of the retarding means thereby retarding movement of the vehicle in the said direction.

2. Apparatus as claimed in Claim 1 wherein the fender comprises an inflatable flexible member containing gas and the sensor is adapted to sense change of pressure of the gas.

3. Apparatus as claimed in Claim 2 wherein the inflatable member is carried by support means.

4. Apparatus as claimed in Claim 3 wherein the support means is adapted to move the inflatable member from a first location adjacent a surface of the vehicle to a second location spaced from the said surface.

5. Apparatus as claimed in Claim 4 wherein the flexible member is elongate and the support means comprises a pair of support members which, when the inflatable member is at the second location, are elongate and extend substantially orthogonal to a longitudinal axis of the inflatable member.

6. Apparatus as claimed in Claim 5 wherein the support members support opposite end portions of the flexible member.

7. Apparatus as claimed in Claim 5 or Claim 6 wherein each support member comprises a flexible tubular member having an elongate resilient strip extending longitudinally thereof, each strip causing each corresponding tubular member to coil upon itself when the flexible member returns from the second location to the first location.

8. Apparatus as claimed in Claim 7 wherein each said tubular member is connected to means for supplying gas to the tubular members.

9. Apparatus as claimed in Claim 8 wherein the circuit includes a third electrical switch for effecting operation of means for supplying gas under pressure from the supply means to the tubular members when the selector is moved to select the predetermined direction of motion of the vehicle.

1 0. Apparatus for effecting operation of retarding means of a vehicle substantially as hereinbefore described and as illustrated in the accompanying drawing.