EP3426216A2

EP3426216A2 - A system for use with a wheeled passenger support

Info

Publication number: EP3426216A2
Application number: EP17718112.0A
Authority: EP
Inventors: Bryce GREENWOOD
Original assignee: Lateral Design Ltd
Current assignee: Lateral Design Ltd
Priority date: 2016-03-09
Filing date: 2017-03-08
Publication date: 2019-01-16
Also published as: WO2017153745A2; GB2548125A; GB201604036D0; WO2017153745A3

Abstract

There is disclosed a system (16) for drawing a wheeled passenger support (17) into a vehicle (10) and selectively restraining the passenger support against movement, and for controlling movement of the passenger support during unloading from the vehicle. The wheeled passenger support may particularly take the form of a wheelchair. One disclosed system comprises a winch (18) comprising a reel (20) and a flexible elongate winch element (22) wound on to the reel, in which the winch is adapted to be located within an interior of the vehicle; a drawing member (24) coupled to the flexible elongate winch element so that, on activation of the winch, the drawing member is pulled towards the winch; at least two restraints (26a, 26b) for the passenger support, the restraints being coupled to the drawing member and adapted for coupling to the passenger support so that, on activation of the winch, the passenger support is pulled towards the winch and so drawn into the vehicle; and a locking assembly (28) which is operable to restrain the drawing member, and the wheeled passenger support coupled to the drawing member, against movement in a direction away from the winch.

Description

A SYSTEM FOR USE WITH A WHEELED PASSENGER SUPPORT

The present invention relates to a system for drawing a wheeled passenger support into a vehicle and selectively restraining the passenger support against movement, and for controlling movement of the passenger support during unloading from the vehicle. In particular, but not exclusively, the present invention relates to a system for drawing a wheeled passenger support such as a wheelchair, wheeled bed or stretcher, into a vehicle and for selectively restraining the wheelchair or the like against movement. It is common practice in modern vehicle design to modify standard road-going vehicles to include systems which provide access for a wheeled passenger support, such as a wheelchair, or a wheeled bed/stretcher, into the vehicle. Typically, the modification process involves installing a lowered floor, and an inclined ramp along which the passenger support can travel to access the vehicle. The ramp is usually either powered and retractable into the body of the vehicle, or provided as a separate component which can be stored in the vehicle and manually deployed when required.

It is necessary to restrain the passenger support within the vehicle, to restrict movement of the support during operation of the vehicle. This is in an effort to prevent injury to the occupant, particularly in the event mat the vehicle is involved in a road traffic accident. This has conventionally been achieved by strapping the passenger support to the floor of the vehicle, using pairs of straps secured to front and rear parts of a frame of the support. The straps extend from the passenger support to anchor points, which are normally provided in the floor of the vehicle. This requires careful positioning of the passenger support within the vehicle, and adjustment of the straps to securely hold the support against movement This can be a fiddly and time-consuming operation. Restraining systems have therefore been developed which seek to address these problems.

One particular system that has been developed comprises a pair of 'electric reels', which operate in conjunction with a winch. The winch is used to draw the passenger support up the ramp and into the vehicle, and has a particular use with bariatric passengers. The electric reels are positioned either side of the winch, and bear the load of the passenger and the support during operation of the vehicle. The electric reels each comprise a strap (of the type found in vehicle seatbelt assemblies) which is wound on to a reel, a sprung retracting mechanism for the strap, and an electrically-operated lock. Typically, the straps are attached at opposed corners of a frame of the passenger support. In the case of a wheelchair, the straps are often attached to corners of a front part of the wheelchair frame, so that the wheelchair is drawn forwards up the ramp.

The lock comprises a ratchet wheel coupled to the reel, and a sprung pawl which engages teeth of the ratchet wheel. This arrangement allows the strap to be reeled-in, but restrains it from being paid-out. The straps are reeled-in by the retracting mechanism as the passenger support is drawn into the vehicle along the ramp, but the lock restricts movement of the support away from the reel, and so is capable of bearing the load of the passenger and the support The lock is typically solenoid-actuated, and arranged to 'fail-safe' to a locked position. In use, solenoids of the locks are activated to release the locking pawl from engagement with the ratchet teeth, so that the straps can be paid-out from the reel, and thus extended for coupling to the passenger support The solenoids are then deactivated, releasing the pawl so that it re-engages the ratchet teeth. The winch is then operated to draw the passenger support up the ramp and into the vehicle. The retracting mechanisms of the electric reels take up the slack in the straps as the passenger support advances into the vehicle. When the passenger support has been located at a desired position within the vehicle, the winch is deactivated. The engagement between the pawls and their respective ratchets has the effect of locking the reels, preventing extension of the straps and so restricting movement of the passenger support A further pair of electric reels, or manual straps, are then coupled to the rear of the passenger support to securely restrain it against movement within the vehicle.

Whilst systems of this type offer improvements over prior arrangements, they still suffer from certain significant disadvantages. In particular and as discussed above, the straps of the electric reels are typically of the type used for vehicle seatbelts, which are designed to permit a certain amount of extension under load. The purpose of this, in the context of a seatbelt, is to extend stopping distance on a wearer under load, thereby reducing the average stopping force on the wearer, compared to a non-stretching belt.

This can be problematic, in the context of restraints for wheeled passenger supports, particularly if the support is positioned off-centre within the vehicle, and so closer to one of the electric reels than the other. This is because the portion of the strap extending between one of the reels and the support is longer than the other. The longer strap experiences a comparatively greater extension under load than the other (shorter) strap, which can result in uneven application of restraining forces on the wheelchair. In addition, the restraining forces imparted on the support by the straps are directed at different angles, relative to the support. These factors can cause discomfort for the user, can make loading unloading of the support to and from the vehicle difficult and, in certain circumstances (such as a road traffic accident), can be dangerous. It is amongst the objects of the present invention to obviate or mitigate at least one of the foregoing disadvantages.

According to a first aspect of the present invention, there is provided a system for drawing a wheeled passenger support into a vehicle and selectively restraining the passenger support against movement, and for controlling movement of the passenger support during unloading from the vehicle, the system comprising:

a winch comprising a reel and a flexible elongate winch element wound on to the reel, in which the winch is adapted to be located within an interior of the vehicle;

a drawing member coupled to the flexible elongate winch element so that, on activation of the winch, the drawing member is pulled towards the winch;

at least two restraints for the passenger support, the restraints being coupled to the drawing member and adapted for coupling to the passenger support so that, on activation of the winch, the passenger support is pulled towards the winch and so drawn into the vehicle; and

a locking assembly which is operable to restrain the drawing member, and the wheeled passenger support coupled to the drawing member, against movement in a direction away from the winch. Typically, the vehicle will be of a type which has been modified to provide access for the wheeled passenger support into the vehicle, for example by installing a lowered floor, and an inclined ramp along which the passenger support can travel to access the vehicle.

Coupling the drawing member to the winch via the flexible elongate element, which may be a single such element of the system, helps to avoid problems with electric reels used in prior systems, where the straps of the reels can end up being of different lengths. In particular, a problem in which uneven restraining forces are imparted upon the wheeled passenger support can potentially be avoided.

Coupling the restraints to the drawing member provides the possibility of the restraints being significantly shorter than the straps of electric reels in prior systems, mitigating problems associated with electric reel straps of different lengths suffering different relative extensions under load.

Reference is made in this document to a wheeled passenger support. The wheeled passenger support may be of any suitable type, including but not limited to: a wheelchair, a wheeled bed; a wheeled stretcher, a mobility vehicle; and a child's buggy, pram or pushchair.

The system may have a use both in the drawing-in of a passenger support and so loading of the support into the vehicle, and for controlling movement of the passenger support during unloading from the vehicle. It will be understood that, to unload the passenger support from the vehicle, the drawing member must be released for movement in a direction away from the winch. During unloading, the winch may be operable to impart a restraining load on the drawing member, to control movement of the passenger support coupled to the drawing member. The flexible elongate element may be paid-out from the reel during unloading. The winch may be operable to arrest movement of the drawing member and so the passenger support. The restraints may act to couple the passenger support to the drawing member, for drawing the support into the vehicle, as well as to restrain the support against movement in a direction away from the drawing member during operation of the vehicle. This may serve to restrict movement of the passenger support in at least a direction away from the winch, during operation of the vehicle.

The restraints may be coupled to the drawing member at locations which are spaced apart along a length of the member. This may provide the ability to impart restraining loads on the passenger support directed along axes which are spaced apart, and which are optionally non-parallel. This may provide for secure restraint of the passenger support during operation of the vehicle. The restraints may be arranged, in use, to converge towards the passenger support.

The restraints may be flexible and elongate. The restraints may be selected from the group comprising: a strap; a tie; a cable; a chain; a rope; and a combination of one or more thereof.

The restraints may be adjustable in length. The restraints may be connected to the drawing member, such as via a threaded bolt or screw. The restraints may be adapted to be releasably coupled to the passenger support, such as via a hook, or a loop of or formed by the restraint. The restraint may comprise a latch provided on an end of the restraint, and a buckle which is engageable by the latch to form a loop which can receive a part of the passenger support

The restraints may be separate/discreet restraints. The system may comprise a restraint assembly, the restraints forming parts of the restraint assembly. For example, the restraint assembly may comprise a frame, or an arrangement of flexible elements (such as a web- type arrangement), the restraints forming elements of the frame or of the arrangement

The restraints may be arranged so that, in use, they exert downwardly directed restraining forces on the passenger support This may be achieved by coupling the restraints to the passenger support at locations which are above the drawing bar, and in particular which are above the drawing bar following actuation of the locking assembly to restrain the bar against movement. The drawing member may be a substantially rigid member. The drawing member may be a bar, rod, plate, or other suitable structure. The drawing member may be a T-bar. The drawing member may comprise a main portion, and an extension portion which extends f om the main portion at a location between opposed ends of the main portion. The extension portion may be adapted to cooperate with a part of the locking assembly. The drawing member may be substantially solid, or may be tubular. The drawing member may be of a metal, metal alloy, plastics material or combination thereof.

The drawing member may be disposed generally transverse, optionally substantially perpendicularly, to the flexible elongate winch element and/or to a pulling direction of the winch/direction of travel of the passenger support during operation of the winch. The drawing member may be elongate, having a main axis. The main axis may be disposed generally transverse to the flexible elongate winch element pulling direction/direction of travel. The drawing member may have a first end and a second, opposite end. One of the restraints may be coupled to the drawing member at a location which is closer to the first end man to the second end. The other one of the restraints may be coupled to the drawing member at a location which is closer to the second end than to the first end. The restraints may alternatively be coupled to the drawing member at a common location, which may be between the first and second ends. The locking assembly may be associated with the winch, optionally so that operation of the winch automatically brings the drawing member into a position into which the locking assembly can operate to restrain the drawing member.

The locking assembly may comprise a lock body and at least one locking element which is actuable between locked and unlocked positions. The locking assembly may be arranged so that the at least one locking element has a fail-safe state, in which it is urged towards the locked position. A locking element may be associated with the lock body and arranged so that, in its locked position, it engages the drawing member. The locking element may be mounted on the lock body.

A locking element may be associated with the drawing member and arranged so that, in its locked position, it engages the lock body. The locking element may be mounted on the drawing member. The lock body may be associated with the winch, and may be coupled to the winch, such as to a housing containing the winch. The lock body may be provided separately from the winch.

The locking assembly may comprise a keeper for the locking element, which may be an aperture, recess or depression shaped to receive a part of the locking element. Where the locking element is associated with the lock body, the keeper may be associated with the drawing member. The keeper may be on or in the drawing member. Where the locking element is associated with the drawing member, the keeper may be associated with the lock body. The keeper may be on or in the lock body.

The locking assembly may be arranged to restrain the drawing member against movement under applied torsional loading. The torsional loading may be about a substantially vertical axis. The torsional loading may be about a substantially horizontal axis, which axis may be transverse to (optionally substantially perpendicular to) the flexible elongate winch element and/or to a pulling direction of the winch/direction of travel of the passenger support during operation of the winch. This may be achieved by providing a locking assembly comprising a plurality of locking elements, which serve to impart restraining loads on the drawing member at locations which are spaced apart along a length of the member. The locking assembly may be arranged so that, in a fail-safe mode, the drawing member is restrained against movement This may be achieved by arranging the at least one locking element to fail-safe to a locked position. The locking assembly may be arranged to clamp the drawing member to restrain it against movement. The locking assembly may comprise at least one clamping surface which is associated with a locking element so that, when the locking assembly is actuated, the drawing member is clamped between the locking element and the clamping surface. The system may comprise a guide for the drawing member, for guiding the drawing member during pull-in towards the winch. The guide may serve for guiding the drawing member towards a restraining location. In the restraining location, the locking assembly may be operable to restrain the drawing member against movement in a direction away from the winch. The guide may serve for guiding the drawing member into a position where the locking assembly can be operated to restrain the drawing member.

The guide may be associated with the winch, and may for example be coupled to or provided as part of a housing of the winch. The guide may be provided separately from the winch. The guide may be associated with the drawing member.

The system may comprise a cooperating member which cooperates with the guide to cause the drawing member to be brought to the restraining location.

Where the guide is associated with the winch or provided separately from the winch, the cooperating member may be on the drawing member. Where the drawing member comprises an extension portion (e.g. where it is in the form of a T-bar), the cooperating member may be, or may be formed by, the extension portion.

Where the guide is associated with the drawing member, the cooperating member may be associated with the winch or provided separately from the winch. The guide may serve for guiding the drawing member in a vertical plane. The guide may serve for guiding the drawing member in a horizontal plane. The guide may serve for guiding the drawing member in both vertical and horizontal planes. The guide may comprise at least one guide surface which is arranged to interact with the drawing member to guide it towards the restraining location.

At least part of the guide surface may be inclined. At least part of the guide surface may be arcuate. The guide may comprise at least one pair of opposed guide surfaces which together act to guide the drawing member towards the restraining location. The opposed guide surfaces may define a channel or recess which receives the drawing member. A dimension of the channel/recess may decrease, in a direction towards the winch.

The guide may comprise at least one guide member, the guide member defining at least one guide surface.

The guide may comprise a lower guide surface, which is arranged to impart a generally vertically upwardly directed force on the drawing member during draw-in, to urge the drawing member generally upwardly. The lower guide surface may be inclined (and may be planar, curved or a combination of such) in a direction towards the winch.

The guide member may comprise an upper guide surface, which is arranged to impart a generally vertically downwardly directed force on the drawing member during draw-in, to urge the drawing member generally downwardly. The upper guide surface may be declined (planar, curved or a combination of such) in a direction towards the winch.

The guide may comprise a left guide surface and a right guide surface, the surfaces arranged to impart generally horizontally directed forces on the drawing member during draw-in. The left and right guide surfaces may be angled in a direction towards the winch, and may be planar, curved or a combination of such. The guide may comprise a guide surface which is shaped to guide the drawing member in both vertical and horizontal planes. The guide may be generally frusto-conical in shape. The guide may be generally circular or elliptical-shaped in cross section. The system may comprise at least one further restraint, for restraining the passenger support against movement in a direction towards the winch.

The flexible elongate winch element may be selected from the group comprising: a strap; a tie; a cable; a chain; and a combination of two or more thereof. The elongate winch element may be a webbing or of a webbing material, in particular a safety belt webbing material.

The system may comprise a remote control, for controlling operation of at least one of the winch and the locking assembly, from a remote location. The remote location may be external of the vehicle.

The system may be an assisted system, which may require an attendant or assistant for aiding and/or controlling loading and unloading of the passenger support into and out of the vehicle.

The winch may be an electrically operated winch comprising a motor, and the system may comprise a limiter which limits driving power of the motor, for example in the event of the passenger support becoming obstructed, particularly during drawing-in to the vehicle. This may serve to restrict injury to an occupant of the passenger support The limiter may be arranged to limit the current that can be drawn by the winch motor.

According to a second aspect of the present invention, there is provided a vehicle comprising a system for drawing a wheeled passenger support into the vehicle and for selectively restraining the passenger support against movement according to the first aspect of the invention. Further features of the system forming part of the vehicle of the second aspect of the invention may be derived from the text set out above relating to the first aspect of the invention. An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of a vehicle of a type which has been modified to provide access for a wheeled passenger support;

Figs. 2, 3 and 4 are front, left side and plan views, respectively, of a system for drawing a wheeled passenger support into a vehicle of the type shown in Fig. 1 and selectively restraining the passenger support against movement, and for controlling movement of the passenger support during unloading from the vehicle, in accordance with an embodiment of the present invention;

Fig. 5 is an enlarged perspective view of the system shown in Figs. 2 to 4; and

Figs. 6, 7, 8 and 9 are perspective views of the system illustrated in Figs. 2 to 5, shown in use, during the drawing-in of a wheeled passenger support on to a test rig representing part of a vehicle of the type shown in Fig. 1.

Turning firstly to Fig. 1, there is shown a perspective view of a vehicle, indicated generally by reference numeral 10, of a type which has been modified to provide access for a wheeled passenger support. The wheeled passenger support can include, but is not restricted to, a wheelchair, a wheeled bed or stretcher, a mobility vehicle, or a child's buggy, pram or pushchair. The vehicle 10 has been modified to include a specially lowered floor portion 12, and includes a hinged ramp 14 which can be folded-up and stored in the vehicle 10 when not required. The ramp can be powered or may be manually deployable. A wheeled passenger support can pass along the ramp 14 and on to the lowered floor 12, and so enter and exit the vehicle 10. Turning now to Figs. 2, 3 and 4, there are shown front, left side and plan views, respectively, of a system for drawing a wheeled passenger support into a vehicle 10 of the type shown in Fig. 1 and selectively restraining the passenger support against movement, and for controlling movement of the passenger support during unloading from the vehicle, in accordance with an embodiment of the present invention. The invention also

encompasses a vehicle comprising the system shown in Figs. 2 to 4. The system is indicated generally by reference numeral 16 in the drawings, and is also shown in Figs. 6, 7, 8 and 9 which are perspective views of the system shown in use, during the drawing-in of a wheeled passenger support in the form of wheelchair 17.

The system 16 comprises a winch 18, comprising a reel 20 and a flexible elongate winch element, in the form of a strap 22, which is wound onto the reel 20. The system 1 also comprises a drawing member, which may be a drawing bar, and which can take the form of a substantially rigid elongate T-bar or plate 24. The drawing bar 24 is coupled to the winch strap 22 so that, on activation of the winch 18, the drawing bar 24 is pulled towards the winch. As will be described below, this facilitates drawing-in of the wheelchair 17 into the vehicle 10.

The system 16 also comprises at least two restraints for the wheelchair 17, the restraints indicated by reference numerals 26a and 26b, respectively. The restraints 26a, b are coupled to the drawing bar 24, and are adapted for coupling to the wheelchair 17 so that, on activation of the winch 18, the wheelchair is pulled towards the winch, and so drawn into the vehicle 10. The system 16 also comprises a locking assembly which is operable to restrain the drawing bar 24 and the wheelchair 17 coupled to the drawing bar against movement in a direction away from the winch, the locking assembly indicated generally by reference numeral 28. In this way, the wheelchair 17 is restrained against movement away from the winch during operation of the vehicle 10.

The system 16 also serves for controlling movement of the wheelchair 17 during unloading from the vehicle 10. Accordingly, the system 16 has a use both in the drawing-in of the wheelchair 17 and so loading of the wheelchair into the vehicle 10, and for controlling movement of the wheelchair 17 during unloading from the vehicle 10. In particular, the system 16 is operable to control descent of the wheelchair 17 down the ramp 14. It will be understood that, to unload the wheelchair 17 from the vehicle 10, the drawing bar 24 is released for movement in a direction away from the winch 18. During unloading, the winch 18 is operable to impart a restraining load on the drawing bar 24, to control movement of the wheelchair 17 coupled to the drawing bar 24. The strap 22 is paid-out from the reel 20 during unloading, and the winch 18 is operable to arrest movement of the drawing bar 24, and so the wheelchair 17.

The system 16, and its method of operation, will now be described in more detail.

Figs. 6 to 9 show a test rig for the system 16, comprising a simulated lowered vehicle floor portion 12, and illustrate the system during an operation to draw-in and restrain the wheelchair 17. The winch 18 is located within an interior 30 of the vehicle 10, and is typically bolted to a major structural component of the vehicle, such as a floor or chassis component, which is indicated by the numeral 31 in the drawings. As can clearly be seen, the winch 18 is typically positioned at an inward end 32 of the lowered floor portion 12.

The flexible strap 22 is typically of a vehicle seatbelt-type material. As best shown in Fig. 7, the flexible strap 22 is paid-out from the winch reel 20, and can be secured to the drawing bar 24 by any suitable means. In the illustrated embodiment, a clamp assembly 33 is coupled to the flexible strap 22, and is fixed to the drawing bar 24 by nut and bolt arrangements, rivets or the like.

Initially, the wheelchair 17 will reside outside of the vehicle 10. With the wheelchair 17 in this position, the winch 18 is put into a deactivated mode, and the flexible strap 22 paid-out from the reel 20, for example by pulling the drawing bar 24 away from the winch. The winch typically has a fail-safe locked state in which the flexible strap 22 is prevented from being paid-out from the reel 20. This can suitably be achieved via a control mechanism associated with the winch 18 (not shown), such as a ratchet and pawl assembly which can be actuated to release the pawl from teeth of the ratchet wheel so that the flexible strap 22 can be paid out.

The restraints 26a, b take the form of flexible straps, again suitably of vehicle seat-belt material, and are connected to the drawing bar 24. Typically, a first one of the straps 26a is connected to the drawing bar 24 towards a first end 34 of the bar, and a second one of the straps 26b connected to the bar towards a second, opposite end 36. Spacing the straps 26a, b in this way is advantageous, as it provides for secure restraint of the wheelchair 17. The flexible restraint straps 26a and 26b can be coupled to the wheelchair 17 in many different ways. In the illustrated embodiment, the restraint straps 26a and 26b are adjustable in length, carrying a buckle 38 (one shown), which engages a latch 40 provided on an end of the strap. The restraint straps 26a, 26b are each passed around a frame 42 of the wheelchair 17, and the latches 40 engaged in the buckles 38 to securely couple the wheelchair to the drawing bar 24.

The winch 18 can then be operated to pay-in the flexible strap 22 on to the reel 20. This pulls the bar 24 towards the winch 18, drawing the wheelchair 17 up the ramp 14 and on to the lowered floor portion 12 of the vehicle 10. Figs. 6 to 9 show the wheelchair 17 during transit along the lowered floor portion 12 towards a restraining location. Figs. 2 to 5 show the drawing bar 24 in the restraining location, in which the wheelchair 17 has been fully drawn-in to the vehicle 10.

In the illustrated embodiment, the drawing bar 24 is a 'T-bar', and is substantially rigid and solid, in the shape of an elongate, generally flat plate. The drawing bar 24 is suitably of a metal, metal alloy, plastics material or combination thereof. The T-bar 24 comprises a main bar portion 44, and an extension portion 46 which extends from the main bar portion 44 at a location between the opposed ends 34 and 36 of the bar 24. As will be described below, the extension portion 46 is adapted to cooperate with a part of the locking assembly 28. The drawing bar 24 is disposed generally transverse to the flexible elongate winch element 22 (typically substantially perpendicular), and to a pulling direction of the winch

18/direction of travel of the wheelchair 17 during operation of the winch. It will be understood, however, that the orientation of the drawing bar 24 ultimately depends upon factors including the position of the wheelchair 17 relative to the lowered floor 12 of the vehicle 10. Transverse orientation of the drawing bar 24 assists in providing smooth passage of the wheelchair 17 along the floor portion 12, and also the application of balanced restraining forces on the wheelchair during use.

In the illustrated embodiment, the locking assembly 28 is associated with the winch 18, so that operation of the winch automatically brings the drawing bar 24 into a position in which the locking assembly can operate to restrain the drawing bar. To this end, the locking assembly 28 comprises a lock body 48 and at least one locking element which is actuable between locked and unlocked positions. The illustrated locking assembly 28 comprises two such locking elements, which are given the reference numerals 50a and 50b.

The locking elements 50a, b are shown in their locked positions in Figs. 2 to 5, and in their unlocked positions in Figs. 6 to 9. The locking assembly 28 is arranged so that the locking elements 50a, b have a fail-safe state, in which they are urged towards their locked positions. The locking elements 50a, b are associated with the lock body 48, and in particular take the form of locking arms which are pivotally mounted to the lock body, for movement between their unlocked and locked positions. In their locked positions, the locking elements 50a, b can engage the drawing bar 24, as can be seen from Figs. 2 to 5.

The locking assembly 28 also comprises respective keepers 52a and 52b for the locking elements 50a and 50b. In the illustrated embodiment, the keepers 52a, b are on the drawing bar 24, and are defined by the extension portion 46 of the bar. The keepers 52a, b take the form of apertures which are shaped to receive parts of the respective locking elements 50a, b. As best shown in Figs. 3 and 4, the locking elements 50a and 50b comprise respective locking teeth 54a, 54b which engage in the keeper apertures 52a, 52b to lock the drawing bar 24 relative to the winch 18. The locking assembly 28 is arranged so that it can restrain the drawing member 24 against movement under applied torsional loading, during use. The torsional loading can be about a substantially vertical axis 56 (Fig. 5), and or a substantially horizontal axis 58. The horizontal axis 58 is transverse (optionally substantially perpendicular) to the flexible elongate winch element 22 and/or to a pulling direction of the winch 18/direction of travel of the wheelchair 17.

This is achieved by the arrangement of the locking elements 50a, b and the way in which they engage the keeper apertures 52a, b in the drawing bar 24, and by arranging the locking assembly 28 so that it clamps the drawing bar. To this end, the locking assembly 28 comprises clamping surfaces 60a, 60b associated with the respective locking elements 50a, 50b so that, when the locking assembly is actuated, the drawing bar 24 is clamped between the locking elements 50a, b and the clamping surfaces 60a, b. The locking assembly 28 is also arranged so that it has a fail-safe mode, in which the drawing bar 24 is restrained against movement. This is achieved by arranging the locking elements 50a, b so that they are urged towards a fail-safe locked position. To mis end, the locking assembly 28 comprises actuators 62a and 62b for the respective locking elements 50a and 50b. The actuators 62a, b comprise respective actuator rods 64a, b which are coupled to the locking elements 50a, b. The actuator rods 64a, b are shown disconnected in Figs. 2 to 5. The actuator rods 64a, b are biased towards extended positions, such as via springs (not shown), so that they urge the locking elements 50a, b into engagement with the drawing bar 24 in the absence of a release force. The release forces can be applied by any suitable means, but are typically applied by solenoids (not shown) of the actuators 62a and 62b.

The system 16 also comprises a guide for the drawing bar 24, for guiding the drawing bar during pull-in towards the winch, the guide indicated generally by reference numeral 66. The guide 66 serves for guiding the drawing bar 24 towards a restraining location, which is that shown in Figs. 2 to 5, where the bar can be engaged by the locking elements 50a, b. The guide 66 is associated with the winch 18, and is coupled to a housing 68 of the winch. The system 16 also comprises a cooperating member which cooperates with the guide 66, to cause the drawing bar 24 to be brought to the restraining location. In the illustrated embodiment, the cooperating member is on the drawing bar 24, and is formed by the extension portion 46 of the T-bar. The illustrated guide 66 serves for guiding the drawing bar 24 in a vertical plane, and comprises at least one guide surface arranged to interact with the drawing bar to guide it towards the restraining location. In the illustrated embodiment, the guide 66 comprises two pairs of opposed, inclined guide surfaces 72a, 74a and 72b, 74b which together act to guide the drawing bar 24 (in particular the extension portion 46) towards the restraining location. The opposed guide surfaces 72a, 74a and 72b, 74b define a channel 76 which receives the drawing bar 24. As best shown in Figs. 3 and S, a dimension of the channel 76 decreases, in a direction towards the winch 18, to urge the drawing bar 24 towards a central position within the channel so that the locking elements 50a, b can engage in the keeper apertures 52a, b.

The guide surfaces 72a, 74a and 72b, 74b are defined by guide members 78a and 78b of the guide 66. The guide members 78a, b effectively form upper guide surfaces 72a, b and lower guide surfaces 74a, b. The upper guide surfaces 72a, b impart a generally vertically downwardly directed force on the bar 24 during draw-in, to urge the bar generally downwardly. The lower guide surfaces 74a and 74b, in contrast, impart a generally vertically upwardly directed force on the bar 24 during draw-in, to urge the bar generally upwardly. The upper guide surfaces 72a, b are declined in a direction towards the winch 18, whereas the lower guide surfaces 74a, b are inclined in a direction towards the winch. The guide surfaces 72a, b and 74a, b are each substantially straight or planar, but may be curved or a combination of straight planar and curved portions.

Optionally, the guide 66 can serve for guiding the drawing bar 24 in a horizontal plane, and optionally in both vertical and horizontal planes. This may be achieved by providing left and right guide surfaces (not shown), arranged to impart generally horizontally directed forces on the bar 24 during draw-in. The left and right guide surfaces may be angled in a direction towards the winch 18, and may be straight/planar, curved or a combination of such. As the wheelchair 17 is drawn into the vehicle 10, the drawing bar 24 approaches the guide 66 associated with the winch 18. Contact between the drawing bar 24 (in particular the extension portion 46) and the guide surfaces 72a, b or 74a, b acts to urge the bar to a central position within the guide channel 76. The locking elements 50a, b are initially in their unlocked positions, this being achieved by operation of the actuator solenoids. The winch 18 continues to operate, to pull-in the bar 24, until such time as the bar is fully seated in the guide 66. The winch 18 will typically automatically cut-out, such as via a load switch (not shown) on the winch coming into contact with the bar 24.

The locking elements 50a, b can then be actuated to move to their locked positions, by deactivating the actuator 62a, b solenoids. The locking elements 50a, b then engage the keeper recesses 52a, b in the bar 24, to restrain the bar against movement away from the winch 18. The bar 24 is firmly clamped between the locking elements 50a, b and the clamping surfaces 60a, b defined by the guide members 78a, b. This resists torsional loading on the bar 24 imparted by the wheelchair 17, during use.

The wheelchair 17 is thus securely held against movement in a direction away from the winch 18, both during normal use of the vehicle and in the event of a crash situation occurring. The system 16 comprises further restraints (not shown), for restraining the wheelchair 17 against movement in a direction towards the winch 18. Typically, standard restraints will be used which extend between the vehicle and the wheelchair 17, and which are typically secured to the other side of the wheelchair, in this case a rear of the wheelchair. Suitably, the further restraints may be secured to the vehicle on or near the lowered floor 12. In this way, the wheelchair 17 is firmly held.

The restraint straps 26a, b are arranged so that, in use, they exert downwardly directed restraining forces on the wheelchair 17. This is achieved by coupling the restraint straps 26a, b to the wheelchair 17 at locations which are above the drawing bar 24, and in particular which are above the drawing bar following actuation of the locking assembly 28 to restrain the bar against movement It will be understood that this is facilitated by positioning the winch 18 low down within the vehicle interior 30, in particular near the level of the lowered floor 12. In this way, when the drawing bar 24 is secured against movement away from the winch 18, the bar is at a similarly low level. This has the result that the restraint straps 26a, b extend upwardly away from the bar 24 towards the wheelchair 17. As a consequence, restraining forces imparted on the wheelchair 17 by the restraint straps 26a, b are directed downwardly, towards the vehicle floor 12. This is beneficial in restricting the wheelchair 17 from leaving the floor 12 in the event of a high loading being experienced, such as during an emergency stop of the vehicle, or in a crash situation. The wheelchair 17 is removed from the vehicle 10 by repeating the above steps in reverse. This may require the interaction of an attendant in order to withdraw the wheelchair 17 from the vehicle down the ramp 14. It will be understood that the winch 18 may be used to lower the wheelchair 17 down the ramp 14. In this regard, the system 16 may be an assisted system, which may require an assistant or attendant for aiding and/or controlling loading and unloading of the wheelchair 17 into and out of the vehicle 10.

The system 16 may comprise a remote control (not shown), for controlling operation of at least one of the winch 18 and the locking assembly 28, from a remote location. The remote location may be external of the vehicle 10.

The winch 18 may be an electrically operated winch comprising a motor 80, and the system 16 may comprise a limiter (not shown) which limits driving power of the motor 80, for example in the event of the wheelchair 17 becoming obstructed, particularly during drawing-in to the vehicle 10. Such may occur, for example, if a main wheel 82 of the wheelchair 17 comes into contact with an obstruction which restricts movement of the wheelchair. This may serve to prevent injury to the wheelchair occupant during loading, by stopping the motor. In particular, the nature of the obstruction may be such that continued operation of the motor could cause the wheelchair to tilt and/or twist and potentially to tip over, risking injury to the occupant. The limiter may be arranged to limit the current that can be drawn by the winch motor 80. Various modifications may be made to the foregoing without departing from the spirit or scope of the present invention.

For example, the guide may comprise a guide surface which is shaped to guide the drawing member in both vertical and horizontal planes. The guide may be generally frusto-conical in shape, and may be generally circular or elliptical-shaped in cross section. The restraints may be arranged, in use, to converge towards the passenger support The restraints may be selected from the group comprising: a strap; a tie; a cable; a chain; a rope; and a combination of one or more thereof. The restraints may be of fixed lengths. The system may comprise a restraint assembly, the restraints forming parts of the restraint assembly. For example, the restraint assembly may comprise a f ame, or an arrangement of flexible elements (such as a web-type arrangement), the restraints forming elements of the f ame or of the arrangement. The drawing member may be a bar, rod, plate, or other suitable structure. The drawing member may be tubular. A locking element may be associated with the drawing member and arranged so mat, in its locked position, it engages the lock body. The locking element may be mounted on the drawing member. The lock body may be provided separately from the winch. Where the locking element is associated with the drawing member, the keeper may be associated with the lock body. The keeper may be on or in the lock body. Embodiments comprising a pair of locking elements are disclosed. In a variation, the system may comprise a single locking element, or more than two. The guide may be provided separately from the winch. The guide may be associated with the drawing member. Where the guide is associated with the drawing member, the

cooperating member may be associated with the winch or provided separately from the winch. The flexible elongate winch element may be selected from the group comprising: a strap; a tie; a cable; a chain; and a combination of two or more thereof. Whilst mention is made of a system comprising at least two restraints, it is within the scope of the invention mat a single restraint be provided. The restraints may be directly coupled to the drawing member, or indirectly such as via a coupling member. Where a coupling member is employed, the two (or more) restraints may be coupled to a common (i.e. single) such coupling member.

Claims

1. A system for drawing a wheeled passenger support into a vehicle and selectively restraining the passenger support against movement, and for controlling movement of the passenger support during unloading from the vehicle, the system comprising:

a locking assembly which is operable to restrain the drawing member, and the wheeled passenger support coupled to the drawing member, against movement in a direction away from the winch.

2. A system as claimed in claim 1 , in which, during unloading, the winch is operable to impart a restraining load on the drawing member, to control movement of the passenger support coupled to the drawing member.

3. A system as claimed in either of claims 1 or 2, in which me restraints are coupled to the drawing member at locations which are spaced apart along a length of the member.

4. A system as claimed in claim 3, in which the restraints are arranged, in use, to converge towards the passenger support.

5. A system as claimed in any preceding claim, in which the restraints are arranged so mat, in use, they exert downwardly directed restraining forces on the passenger support.

6. A system as claimed in any preceding claim, in which the drawing member is a substantially rigid member.

7. A system as claimed in any preceding claim, in which the drawing member comprises a main portion having opposed first and second ends, and an extension portion which extends from the main portion at a location between the opposed ends.

8. A system as claimed in claim 7, in which the extension portion is adapted to cooperate with a part of the locking assembly.

9. A system as claimed in any preceding claim, in which the drawing member is disposed transverse to the flexible elongate winch element.

10. A system as claimed in any preceding claim, in which the locking assembly is associated with the winch, so that operation of the winch automatically brings the drawing member into a position into which the locking assembly can operate to restrain the drawing member.

11. A system as claimed in any preceding claim, in which the locking assembly comprises a lock body and at least one locking element which is actuable between locked and unlocked positions.

12. A system as claimed in claim 11 , in which the locking assembly is arranged so that the at least one locking element has a fail-safe state, in which it is urged towards the locked position.

13. A system as claimed in either of claims 11 or 12, in which a locking element is associated with the lock body and arranged so that, in its locked position, it engages the drawing member.

14. A system as claimed in claim 13, in which the locking element is mounted on the lock body.

15. A system as claimed in either of claims 11 or 12, in which a locking element is associated with the drawing member and arranged so mat, in its locked position, it engages the lock body.

16. A system as claimed in claim 15, in which the locking element is mounted on the drawing member.

17. A system as claimed in any one of claims 11 to 16, in which the locking assembly comprises a keeper for the locking element.

18. A system as claimed in claim 17, in which the keeper is an aperture shaped to receive a part of the locking element

1 . A system as claimed in any preceding claim, in which the locking assembly is arranged to restrain the drawing member against movement under applied torsional loading.

20. A system as claimed in claim 19, in which the locking assembly comprises a plurality of locking elements, which serve to impart restraining loads on the drawing member at locations which are spaced apart along a length of the member.

21. A system as claimed in any preceding claim, in which the locking assembly is arranged so that, in a fail-safe mode, the drawing member is restrained against movement

22. A system as claimed in any preceding claim, in which the locking assembly is arranged to clamp the drawing member to restrain it against movement, the locking assembly comprising at least one clamping surface which is associated with a locking element so that, when the locking assembly is actuated, the drawing member is clamped between the locking element and the clamping surface.

23. A system as claimed in any preceding claim, comprising a guide for the drawing member, for guiding the drawing member towards a restraining location during pull-in towards the winch.

24. A system as claimed in claim 23 in which, in the restraining location, the locking assembly is operable to restrain the drawing member against movement in a direction away from the winch.

25. A system as claimed in either of claims 23 or 24, comprising a cooperating member which cooperates with the guide to cause the drawing member to be brought to the restraining location.

26. A system as claimed in any one of claims 23 to 25, in which the guide serves for guiding the drawing member in at least one of a vertical plane and a horizontal plane.

27. A system as claimed in any one of claims 23 to 25, in which the guide comprises at least one guide surface which is arranged to interact with the drawing member to guide it towards the restraining location.

28. A system as claimed in claim 27, comprising at least one pair of opposed guide surfaces which together act to guide the drawing member towards the restraining location.

29. A system as claimed in either of claims 27 or 28, in which the guide comprises a lower guide surface which is arranged to impart a generally vertically upwardly directed force on the drawing member during draw-in, to urge the drawing member generally upwardly.

30. A system as claimed in any one of claims 27 to 29, in which the guide member comprises an upper guide surface, which is arranged to impart a generally vertically downwardly directed force on the drawing member during draw-in, to urge the drawing member generally downwardly.

31. A system as claimed in any one of claims 27 to 30, in which the guide comprises a left guide surface and a right guide surface, the surfaces arranged to impart generally horizontally directed forces on the drawing member during draw-in.

32. A vehicle comprising a system for drawing a wheeled passenger support into the vehicle and for selectively restraining the passenger support against movement according to any one of claims 1 to 31.