GB2579076A

GB2579076A - Safety system

Info

Publication number: GB2579076A
Application number: GB1818810.2A
Authority: GB
Inventors: Bowen-Dawes James
Original assignee: DAWES HIGHWAY SAFETY Ltd
Current assignee: DAWES HIGHWAY SAFETY Ltd
Priority date: 2018-11-19
Filing date: 2018-11-19
Publication date: 2020-06-10
Also published as: GB201818810D0

Abstract

Disclosed is a safety system for a public service vehicle (e.g. buses and trams). It has a pneumatic supply, a control device, and at least one inflatable tube section (2,4,6,8,10) mounted in line with the bodywork of the vehicle. The tube section is connected to the pneumatic supply to enable them to be inflate or vented under control of the control device. The tube section may be mounted between the wheel arches on the sides of the vehicle as well as mounted on the front of the vehicle. At least two tube sections may be interconnected by an air pipe 22 to create a separately controllable module which can be inflated/vented independent of the remainder of the system. The system may also include a sensor for detecting immoveable obstacles and enabling partial or full venting in response. The tube sections may also have brushes to skim the road surface. This invention allows pedestrians and cyclists to be deflected away from the underside of the vehicle, thereby preventing limbs from being driven over, whilst also allowing the system to be deflated when the vehicle “kneels” to allow level access for passengers.

Description

Safety system

Technical Field

[1] The present invention relates to vehicle safety systems for minimising the injury to pedestrians when encountering vehicles. More particularly, the invention relates to systems for public service transport vehicles such as buses and street tram cars.

Prior Art

[2] Barriers that prevent a pedestrian or other person slipping beneath a vehicle have been proposed in various designs. Particular problems that need to be overcome with such barriers include the ability to deal with uneven road surfaces and other immovable objects such as sleeping policeman in the road surface [3] A number of solutions have been proposed, particularly for lorries and vehicles with higher ground clearance than is typical for buses. Reference may be made to the applicant's earlier GB 254 0467 published on 18 January 2017 (Dawes) which describes the issues and a solution for commercial vehicles using a retractable inflatable shield made of multiple drop stitch segments and fitted with a brush element to skim the road surface.

[4] WO 2017/066076 Al published 20 April 2017 (Barron) describes a system for buses which uses a resiliently mounted guard piece mounted as a skirt down the side of the bus between the wheel arches. The skirt is intended to deflect the pedestrian and provides a hard impact surface. This system also leaves the risk areas forward of the front wheels exposed Technical problems [5] Buses and street tram cars may have the facility to kneel to allow level entry at stops and the safety system must not inhibit this functionality. There is therefore a need for a safety system that can overcome this problem and allow the vehicle to move safely even over uneven road surfaces containing immovable object, and yet provide an effective barrier to prevent or reduce pedestrian injury.

Solution of the Present Invention [6] The invention is defined in the appended claims.

171 A preferred embodiment of the safety system for a public service vehicle comprises a pneumatic supply, a control device and inflatable tube sections mounted in-line with bodywork of the vehicle between the wheel arches at the side of the vehicle, and at least one forward tube section mounted to the side of vehicle forward of the front wheels, the tube sections being connected directly or indirectly to the pneumatic supply to enable to the tube sections to be inflated or vented under the control of the control device.

181 Other features of the invention are defined in the dependent claims.

Description of the Drawings

191 In order that the invention can be well understood, an embodiment thereof will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which: [10] Figurel shows a side view of the system fitted to a bus, [11] Figure 2 shows an underneath diagrammatic plan view of the system of Figure 1 and [12] Figure 3 shows a detail of the mounting for tube sections of the system

Description of an Embodiment

[13] The system of the invention provides a barrier to deflect any part of a pedestrian from entering underneath a bus. The system provides an inflatable tube comprising sections 2,4,6,8,10 fixed to the lowermost parts of the skirt of a bus and connected to a pneumatic control supply 20 controlled by a control box or device to allow the tube to be inflated and maintained under pressure and at least partially deflated when the bus kneels to allow level access for passengers at the front of the bus. The sections of the tube on either side of a wheel arch 2,4 are interconnected pneumatically by means of an air tube 22 passing behind the wheel so that all the sections are pneumatically interconnected so that the barrier acts as one. The use of such a resilient barrier allows a fallen cyclist or pedestrian to be deflected away from the danger of the buses wheels and will reduce accidents that can be serious even when a hand or foot is driven over.

[14] The system is primarily intended to be fitted to new build passenger buses and street tram cars where the control system can be integrated with that of the vehicle. However, the system can also be retrofitted to existing vehicles.

[15] The barrier is created from individual tube sections. Each tube section is a single tube and is sufficiently resilient that there is no need for it to be retractable as in the multiple tube arrangement of Dawes. Each section is arranged so that its external profile lines up with the skirt or bodywork of the vehicle. The sections are made of polyurethane material drop stitch sections so that the side walls are interconnected to provide a defined shape to the inflated section. Each section has a fixed rod inserted at the top of the tube section that is mounted to a bracket, channel plate 30 attached to the underside of the vehicle the vehicle such as shown in Figure 3. The rod provides a rigid coupling with the bracket or channel plate 30. Fixings of this type are known in the art and will not be described in further detail.

[16] The underside of the tube section that is closest to the road is provided with an extruded aluminium brush holder section that carries a brush 32 that makes contact with the road surface.

[17] When the tubes sections are inflated to lbar or 10 kPa (circa 13.5PSI) of pressure the single tube arrangement forces itself downwards towards the road surface and touches the brush 32 on the road.

[18] A pneumatic supply 50 is connected to the main vehicle pneumatics. The side tube sections 2,4 and front tube section 6 are individually directly connected to the supply by air tubes or pipes 52, 54. The two side sections are interconnected as a single module by means of the air pipe 22. The modular system allows different areas on the vehicle to be controlled separately without the requirement for additional control boxes or additional weight to the vehicle.

[19] The pneumatic supply 50 will be supplied from the existing auxiliary air tanks already present on the vehicle and mounted on/in/beneath the vehicle.

Workings of the system [20] When the ignition of the vehicle is switched into the ON position a 12/24 volt feed will be sent to the control box that will OPEN the main air control manifold and allow air pressure to port from the air tanks of the vehicle through the regulator and control manifold. This air pressure will then enter the system through a main feed pipe to the pneumatic supply 50 of the system. Where the system comprises more than one section (for example at the front 6 and sides of the vehicle) the air will enter each section at an equal speed. Once the air system reaches the required pre-set pressure the manifold will CLOSE and prevent further air entering the system Failures and damage prevention [21] The system once inflated to pressure will show a positive signal to the driver such as green bulb or symbol. If a fault should occur this will display red and an alarm will sound intermittently to alert the driver of the system's failure.

[22] The system will be fitted with a pressure relief valve. Therefore if for any reason the system should enter a state where it could become over pressurised due to mechanical fault, the pressure relief valve will vent the excess pressure to atmosphere from the exhaust inside control box 50 beneath the vehicle and prevent rupture or explosion.

[23] If the tube sections should become damaged, ripped, cut or torn for any reason the system will recognise that it is in a state of failure due to the amount of air volume passing through the regulator in the pneumatic supply 50. This will cause it to shut off its feed from the vehicle thus preserving air pressure within the vehicles air tanks and allowing other air fed systems such as brakes and doors to continue to work. Because the system is unable to retract the empty tube will hang idle in position below the vehicle and not inhibit the vehicle's ability to move. However in this state the fault/warning alarm in the cab will alert the driver to this failure so that it may be reported for repair.

Operation of vehicle fitted with safety system [24] This non-reactive system is designed to be fully automated and will not require any interaction from the driver or vehicle operator. However a manual over-ride switch will be present for servicing or access requirements [25] The system once inflated to pressure will remain solid and not prevent the vehicle's passage over immovable objects on the road surface.

[26] If a moveable object, particularly human being or bicycle should be on the road surface in the path of the vehicle whether turning or going straight ahead the system will prevent it passing and entering the area beneath the vehicle. Where an object is immoveable and fixed to the road such as raised iron work or 'speed bump' the brush affixed to the bottom of the tube sections closest to the road will compress the tube section in an upwards motion (towards the body of the vehicle). This will cause the pressure inside the system to be relieved by doing one of two things: * Excess pressure build up will be transferred to another part of the system where the air pressure is not equal, or * The system will over-pressurise in its entirety causing both the control valve and the exhaust manifold to relieve the excess pressure to atmosphere.

[27] Once the immovable object/obstruction has passed the system will be in an under-inflated state. At this point the system will recognise this and re-open the control manifold allowing the air pressure to increase back up to pre-set operational levels.

Additional Sensor system [28] A sensor system 60 can be mounted to the front of the vehicle to identify immovable objects such as raised ironworks and cause the system to deflate prior to striking it.

Kneeling function [29] There is a requirement for the system to cope with features such as the 'kneeling facility' on a bus where the front of the bus lowers itself to pavement level on order for passengers to board. The system will have an electronic feed from the wiring of the vehicle so that when it enters the 'kneeling' position for passengers to board or alight, the system will deflate and not become crushed by the weight of the vehicle.