WO2008138138A1

WO2008138138A1 - Wheelchair

Info

Publication number: WO2008138138A1
Application number: PCT/CA2008/000931
Authority: WO
Inventors: Myron John Zarry
Original assignee: Myron John Zarry
Priority date: 2007-05-14
Filing date: 2008-05-14
Publication date: 2008-11-20

Abstract

The present disclosure relates to a wheelchair for use in an aircraft for transferring a person with restricted mobility (PRM) to a seat of the aircraft located adjacent the wheelchair. The wheelchair has a base with a base rail that has a horizontal surface arranged in the transfer direction. A support frame bears against the horizontal surface and includes an attachment support structure extending partially over the base to support the PRM. An extension rail can be connected to the wheelchair adjacent the base rail to form a contiguous surface that the support frame can move along. The extension rail may be placed in front of or behind the seat to allow the PRM to be transferred from the wheelchair to the seat.

Description

WHEELCHAIR

TECHNICAL FIELD

The present invention relates to the field of wheelchairs, and in particular to a wheelchair for transporting a passenger with restricted mobility (PRM) to and from an air terminal and a seat on an aircraft and optionally for transporting the passenger within the terminal.

BACKGROUND

Transporting a physically challenged person down the narrow aisle of a commercial passenger aircraft is a challenge. Airline passengers requiring a wheelchair are generally boarded first on, and last off an aircraft, with the assistance of flight attendants and transferred from a narrowly designed wheelchair (typically referred to as a "Washington" chair) to a designated seat on the aircraft. Typically this is an aisle seat, as this is the closest for manual lifting. It is virtually impossible to maneuver a conventionally sized wheelchair down the narrow aisle of a commercial airliner.

Furthermore, currently available wheelchairs for use in the narrow aisles of aircrafts require the passenger to be wheeled to the appropriate seat row and then lifted by flight attendants into the passenger's appropriate seat. This involves a lot of jostling of the passenger resulted in some instances in physical injury to the flight attendants and possibly the passenger, and generally requires at least two or more flight attendants.

Another difficulty faced by passengers with limited mobility is when transported within the airport, for example between terminals or boarding gates. Again, this generally involves transferring the passenger from their seat in the aircraft to a narrow wheelchair which is maneuverable in the narrow aisle and then retransfeπing the passenger to a second wheelchair in the terminal for transport to the next terminal or gate. The narrow wheelchairs used to transfer the person from the aircraft may not provide sufficient stability, due to their narrow base, to allow safe traveling within the terminal. Once at the next terminal or gate the passenger must once again be moved from the transporting wheelchair to the narrow wheelchair, wheeled to the appropriate row and once again physically lifted by flight attendants into their seat. Accordingly, there is a need for a wheelchair for transferring a passenger with restricted mobility to or from their seat in an aircraft and with minimal effort required by a flight attendant. There is a further need for a wheelchair for transferring a passenger with restricted mobility to or from a seat. SUMMARY OF THE INVENTION

In accordance with the present disclosure there is provided a wheelchair comprising a base having at least a pair of wheels for engaging a deck surface and a chair for supporting a person with restricted mobility (PRM) on the base and a support frame releasably coupled to the base. The support frame has an attachment support section for positioning and carrying a connector in proximity to a supported PRM, the connector for releasably coupling to a PRM support harness, and a bearing section at a lower end of said support frame for carrying along said deck said support frame from a position on said base to a position along side said base whereat a coupled PRM may be deposited.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the present disclosure will now be described, by way of example only, with reference to the following drawings in which:

Figure 1 shows a side view of passenger seats in a typical aircraft; Figures 2 shows a block diagram of components of a wheelchair transfer system; Figures 3 a and 3b show a preferred embodiment of a wheelchair transfer system; Figures 4a, 4b and 4c show a top, side and front view of the support frame respectively;

Figure 4d shows a detailed view of a bearing section of the support frame; Figures 5a, 5b and 5c show respective top, side and front views of the support frame positioned with a PRM seated on the wheelchair according to an embodiment of the invention;

Figures 6a and 6b show respectively the support frame is an aisle position and in a position at the aircraft seat; Figure 6c shows a side view of the support frame in relation to the seats of the aircraft; Figures 7a, 7b and 7c show respectively front, top and side views of the transfer extension rail; Figures 8a and 8b show respectively a side and front view a further embodiment of a transferring wheelchair; Figures 9a, 9b and 9c show steps in a sequence moving from a lower surface to an upper surface;

Figures 10a, 10b and 10c a further embodiment of a base of the wheelchair; Figure 11 shows a detailed view of a chair support and width adjustment means; and Figure 12 shows a top view of an extension rail.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description like numerals refer to like structures in the drawings.

The present apparatus and method is described in the context of transferring a passenger from a wheel chair to a seat on an air craft, however this is merely exemplary. I t may be appreciated that the present invention may be applied to other instances where a wheel chair bound person needs to be moved in a restricted space.

Referring to Figure 1 a side view of passenger seats in a typical aircraft (not shown), in this case a Dash-8 aircraft is shown generally by reference numeral 100 As may be seen the passenger seats 102 have their backrests 104 spaced 106 at about 2'6" apart with legroom 108 of about 11(3/4)" and headroom 108 of only about 4'11" above a deck 110 or floor of the aisle. Seats are arranged on either side of an isle which are typically 15' wide. As may also be seen the height 112 of a seat arm rest is typically 2' off the deck 110, thus a passenger must be lifted at least over the arm rest to be placed in a seat. In some instance however the arm rest may be folded up so that the passenger need only be raised as high as the aircraft seat, the height 112 of which is typically 1'5(1/4)** off the deck 110. The transferring wheelchair maybe dimensioned to travel down aisles of other sizes. . Although the wheelchair described in the present embodiments is described in the context of transferring passengers within aircraft, it is understood that the wheelchair could be used in other situations in which the person with restricted mobility must be transferred to or from an adjacent location that has limited space.

Referring to Figures 2 there is shown a block diagram of, components of a wheelchair transfer system 200 for transferring a person with restricted mobility to or from an aircraft seat (not shown), according to a general embodiment of the present invention. The wheelchair transfer system 200 comprises a wheelchair 205, a support frame 225 moveable on a transfer extension rail 240. The wheelchair 205 has a width dimensioned to move along the aircraft aisle, and comprises a base supporting on an upper surface a chair 207 and at a lower portion wheels 209. The base 211 has affixed thereto at a lower front (or rear) section a base rail 215 extending substantially across the base and in proximity to the floor, but not necessarily in contact with the floor. The base rail includes an extension connector 221 at one end thereof. The extension connector 221 has a pocket sized to receive a base connector 242 of a transfer extension rail 240 contiguous with the base rail. The extension rail 242 is positioned relative to the base 211 such that it extends across the floor of the legroom space 108, either in front of or at the rear of the aircraft seat 102.

The support frame 225 has a bearing section 227 at a lower end thereof, with a channel 229 to slideably move over the base rail 215 and the base rail extension 240 when the support frame 225 is positioned over the base rail 215. The support frame 225 includes a vertical support structure 235 which extends upwardly from the bearing section 227, which in turn has at an end thereof an attachment support structure 237 for carrying a passenger hamess(not shown) coupling 232 for lifting a passenger and for positioning the coupling 232 for attachment to the passenger harness for lifting a passenger seated on the chair 207. The overall height of the support frame is chosen so that it may easily be positioned within the headroom space of the aircraft.

The transfer extension rail 240 is sized to match the base rail 215 so that when the base connector 242 of the transfer extension rail 240 is received by the extension connector 221 of the base rail 215, the transfer extension rail and the base rail form a contiguous transfer rail. The transfer extension rail is supported on the legroom floor to extend from the base either in front or behind the aircraft passenger seat and is positioned to allow the support frame to be moved from the chair laterally to the base to the desired aircraft passenger seat. The support frame 225 can be moved along the contiguous transfer rail to position the support frame 225 in a transport position where the moveable support frame 225 is located over the chair 207 of the wheelchair 205, or in a transfer position where the moveable support frame 225 is located over a seat in an aircraft into which the person is being lowered or other location the person with restricted mobility is being transferred to or from, for example their own wheelchair.

In general the moveable support frame 225 connects to one of many know transfer harnesses thus supporting the person under the moveable support frame 225. The transfer harness connector 232 for connecting a harness that secures and supports the person during the transfer operation. A means for raising and lowering the transfer harness connector 232 to facilitate the transfer of the person from the chair 207 of the wheelchair 205, to the seat of the aircraft may also be provided with the support frame. The transfer harness connector 232 may be disconnected from the support harness - supporting the person once the person is lowered into their seat and the transfer operation is completed. Transfer harnesses are well known and will not be discussed further.

Referring to Figures 3 a and 3b there is shown a preferred embodiment of a wheelchair transfer system when deployed for a PRM transfer according to the present invention. In Figure 3 (a) the support frame is shown in position for lifting or lowering a PRM on the seat 307 and Figure 3(b) shows the support frame in position for lowering or raising the PRM on or off a passenger seat(not shown). In this preferred embodiment, the wheel chair transfer system is similar to that as illustrated and described with respect to Figure 2, but includes U-shaped support frame 325 or arch, which in addition is movable on a front 315a and back 315b set of base rails and corresponding transfer extension rails 340 and 342. This embodiment is capable of providing a more stable and lighter support frame than the embodiment depicted with respect to Figure 2. As mentioned the wheelchair 305 is similar to the wheelchair 205 described above with respect to Figure 2, however it has been modified to include two base rails 315a and 31 Sb. The two base rails 315a, 315b are located at generally front and back ends, respectively of the base 311 and are spaced to allow their corresponding extension rails 340 and 342 to be positioned in a front and rear leg room space of the seat to which the PRM is being transferred, thus allowing the support frame 325 to slide on the extension rails, but over the passenger seat 102( as is more clearly shown in Figures 6, to be described later).

The support frame 325 is similar to the moveable support frame 125 described above, however it has been modified to form an arch. The support frame 325 comprises a front and back vertical support sections 336a and 336b. Each of the vertical support sections has a corresponding bearing section 327a and 327b respectively at a lower end. The two vertical support sections 336a and 336b are connected at an upper end by a attachment support structure 337. The bearing sections 327a and 327b may include a bushing or other means, such as roller bearings, for reducing friction and facilitate moving the support frame 325 along the extension rails 340, 342 created by securing the transfer extension rail adjacent to the base rails 315a and 315b.

The support frame 325 has an inverted U shape or arch and is sized so that one of the vertical support sections 336a fits in front of a row of aircraft seats while the other vertical support section 336b fits behind the row of aircraft seats, with the transfer support structure 337 connecting the two vertical sections 336a, 336b passing over the top of the seats of the row and fits within the given headroom 108 of the aircraft.

Referring now to Figures 4a there is shown a top view of the support frame 325 in a preferred embodiment, showing a preferred implementation of the attachment support structure 337. The attachment support structure 337 includes a centering projection 438, which projects in front of the PRM generally over the PRM's chest area, when the transfer frame is positioned over the seat of the wheelchair 305. The centering projection 438 allows the transfer harness connector 132 to connect to a support harness (not shown) at an approximate lateral center of the person being transferred so as to allow for greater stability of the PRM during transfer. In addition, referring to Figure 4b and 4c there is shown a respective side and front view of the support frame 325, As may be seen the vertical support sections 336 a and 336b are arranged to be to one side of the wheel chair 305 (i..e. at the left hand side of the PRM), thus reducing the obstruction to the PRM's vision. A left hand sided version could be used as well, depending on which seat the PRM is being transferred to or from (i.e. starboard or port side).

The support frame 325 may comprise a cable 431 for raising and lowering the harness attachment connector 132 and a motor 433 for extending or retracting the cable 431. The cable 431 passes through the support frame 325 to an exit in the centering proj ection 438. The one end of the cable 431 is connected to the transfer harness connector 132 at one end and the motor 433 at the other end. The motor 433 may be housed in the vertical support section 336b. The cable 431 may pass through a series of guides or pulleys to the centering projection 438 (or to a location in the attachment support structure if the centering projection is not used). Thus the transfer harness connector 132 may be raised and lowered. This in turns allows the PRM coupled via a suitable harness to be raised and lowered to/from a seat (either the chair of the transferring wheelchair or a seat located adjacent the transferring wheelchair). While a cable and pulley system is shown, any other means for raising and lowering the transfer harness connector 132 a sufficient amount to avoid obstructions such as armrests or if armrest can be raised, then seats, may be used. Alternatively, if there are no obstructions in the transferring path, or if the obstructions are of such a height that the person may be released from the height required to pass over the obstacles with out being injured, a fixed position transferring system connected to the transfer harness connector 132 may be used. For example, a fixed length of cable connected to the centering projection 438 and the transfer harness connector 132 may be used.

Referring now to Figure 4d there is shown in greater detail the bearing section 327 of the support frame 325. The bearing section 327 comprises a roller bearing 450 for riding on the bearing surface of the extension and base rails and is connected to the bearing section by an axle 452. The roller bearing 450 has enlarged ends that engage sides of the base rail 315 (or transfer extension rail 340). The enlarged ends of the roller bearing 450 prevent or restrict lateral movement of the support frame 325 with respect to the base rail 315 or transfer extension rail 340. The bearing section 327 comprises two rail capture sections 455a, 455b which project toward and are located below a lip of the base rail 315 or transfer extension rail 340. In other words, a channel 429 is formed between the two rail capture sections 455a and 455b. The rail capture sections 455a, 455b secure the support frame 325 to the base rail or to the transfer extension rail 140 and prevent the support frame 325 from coming off the extension rails during transfer of a person, to help prevent injury to the person. Furthermore, as shown in Figure 4c a pair o roller bearings 450 is shown at respective ends of the bearing section 327.

Referring to Figures 5a, 5b and 5c there is shown a respective top side and front views of the support frame 325 positioned with a PRM seated on the wheelchair 305 . In addition, Figures 5b and 5c show the base of the wheelchair 305 having a center load bearing wheels 509 (or pair of wheels) as well as two pairs of support castors 510. The support castors 510 are located generally at each of the four comers of the base of the wheelchair 305. Figures 5b and 5c show an outline of a person 560 in the chair of the transferring wheelchair 305. However a single front and back castor may be used as well.

Referring to Figures 6a and 6b there is shown respectively the support frame 325 in an aisle position and in a position at the aircraft seat. The wheelchair 305 and support frame 325, as well as the PRM 560 being transferred are shown in figure 6a in the transport position. In the transport position, the support frame 325 is positioned above the wheelchair 305 on the base rail and can be secured in position using a pin or other suitable attachment. The wheelchair 305 can be maneuvered into position by grasping the support frame or the base. Alternatively a motorized mechanism may be provided which may be controlled by the PRM. A further advantage of the support structure is that it is aligned to one side of the base, thus allowing clearer visibility of the PRM, for example if used in an aircraft the wheelchair 305 can be positioned adjacent the appropriate row of seats 102. Once in position the wheelchair 305 may be secured in position, for example using a friction lock on one or more of the wheels. It may not be necessary to use a lock or brake to secure the position of the wheelchair 605. The transfer extension rails 340 and 342 are attached to the wheelchair 325 to form a contiguous transfer rail that the support frame 325 can be moved along.

The PRM 560 is secured to the support frame 325, for example using the appropriate support harness that can be releasably secured to the transfer harness connector 132 which in turn is connected to the cable 431 for raising and lowering the transfer harness connector 132. The transfer extension rail 340 and 342 are positioned in place by placing one of the transfer extension rails in front of the seat and the other behind the seat 102. The transfer extension rails are connected to the base rail (or base rails if both extension rails 340 and 342 are used) to form a contiguous surface or rail that the bearing section of the support frame can be moved along. With the PRM 560 secured to the support frame 325, and the transfer extension rail 340 and 342 in place, the support frame 325 is moved along the extension rail 640 portion of the contiguous transfer rail to the transfer position in which the PRM 560 is located above the aircraft seat 102 they are being transferred to. The motor 435 may then be operated to lower the harness connector 132 and the PRM 560 to the seat 102. The support harness may then be disconnected from the transfer harness connector 132, the support frame 325 returned to the transport position and the transfer extension rails disconnected from the wheelchair 305.

Figure 6c depicts in a schematic the size of the support frame 325 in relation to the seats 102. It is clear from the figure that one vertical support section 436b is located behind the row of seats 102, while the other 436a is located in front of the row of seats 102 . In this arrangement two extension rails would be secured to the wheelchair during transfer, one in front of the row of seats, and one behind the seats.

It may be possible to use the moveable support frame 325 with only a single transfer extension rail. In such a case one of the bearing sections (for example the bearing section 327 located behind the row of seats) can bear upon the ground or deck of the aircraft. The bearing section 327 could also be replaced with a wheel or wheels to make sliding on the ground easier during the transfer operation, Referring to Figures 7 a, 7b and 7c there is shown respectively front top and side views of the transfer extension rail 340, The transfer extension rail 340 comprises a horizontal surface 741, when deployed, a base connector 742 located at one end of the horizontal surface 741, and a foot 745 at the other end of the horizontal surface 741 , The base connector 742 is shown as being a reduced sized in cross-section of the transfer extension rail 340. The reduced sized section of the base connector 342 may index into a corresponding pocket on the base rails 315a, 315b. The indexing helps to ensure that the horizontal surface 741 of the transfer extension rail 340 and a corresponding horizontal surface of the base rail form a contiguous transfer rail to allow the support frame 325 to move between the transport and transferring positions. Other means for connecting the transfer extension rail 340 to the wheelchair 305 are possible, such as a pin and hole arrangement. Alternatively, it is possible that the transfer extension rail 340 is not connected to the transferring wheelchair during the transfer operation. This may require that the transfer extension rail 340 be supported sufficiently on the ground so that it does not move in relation to the wheelchair 305 during the transfer operation so the horizontal surface 741 of the transfer extension rail 340 forms a contiguous surface with the corresponding horizontal surface of the base rail 315a or 315b. The base connector 742 may include a lock 743 for securing the transfer extension rail 340 to the wheelchair 305. The lock 743 depicted in Figure 7a and 7c locks the transfer extension rail 740 into the base of the transferring wheelchair with a turn of a lever.

The foot 745 of the transfer extension rail may be a flat platform or may include a wheel for facilitating positioning of the transfer extension rail. The foot 745 of Figure 7a, 7b and 7c includes two ball rollers 746. The ball rollers 746 may retract into the foot 745 at a particular weight, for example 75 pounds, in order to minimize point loading on the ground or cabin deck on which they rest. This may help prevent damage to composites that may be used in aircrafts. Advantageously, the extension rail provides a flat and smooth horizontal surface to facilitate the movement of the support frame during the transfer operation. If the bearing sections of the support frame do not bear upon the extension rails 340, but instead bear upon a surface that is not smooth for example the deck of the aircraft, care must be taken to prevent sudden stops in the movement of the support frame which could cause the support frame to rotate and potentially tip. Typically ridges or channels may be found on the deck which may cause tipping of the support fram if movd directly on the deck. Thus by using the extension rails a smooth surface for movement of the support frame is ensured. Further by having the extension rails slightly elevated off the deck ensure that any ridges or channels in the deck are avoided.

Referring to Figures 8a and 8b there is shown respectively a side and front view of a further embodiment of a wheelchair 305 according to the rpesent invetion. In this embodiment , the base 811 of the wheelchair 305 includes a stepping means 875 that allows the wheelchair 305 to pass over a step, for example as may be found at the junction of an aircraft and apron. The base 81 1 of the wheelchair 305 has a pair of center load bearing wheels 809a and 809b positioned at the left and right sides (relative to a sitting position of the PRM on the chair) of the base. One of the load bearing wheels 809a is located on a first side of the base 811, and the other load bearing wheel 809b is located on the other side of the base 811. The base also includes support wheels 810 located towards the corners of the base 811 of the wheelchair 305. The stepping means 875 of the base 811 includes two stepper sections 880a, 880b, located respectively in front of and behind the center load bearing wheels 809a,b. The stepper sections 880a, 880b each comprise a stepper wheel 882a, 882b (or pair of wheels) connected to a height adjuster 884a, 884b. The height adjuster 884a, 884b may be for example a linear actuator or motor. The stepper wheels 882a, 882b may be pivotally connected to a common point such as the axle of the center load bearing wheels 809a,b.

Referring to Figures 9a, 9b and 9c there is shown a sequence of operation of the stepper means 875. The height adjusters 884a, 884b are lowered, raising the wheelchair 305 onto the stepper wheels 882a, 882b of the stepper sections 880a, 880b to a height sufficient such that the support wheels 810a, 810b located towards the front of the base 811 of the wheelchair 305 clear the step. As shown in figure 9a, the wheelchair 305 is then moved forward so that the front of the transferring wheelchair 805 is supported on the step by the front support wheels 810. As shown in figure 9b the height adjuster 884a of the front stepper 880a is retracted and the transferring wheelchair 805 is moved forward again so that the center load bearing wheels 809a,b are supported on the step. As shown in figure 9c the back height adjuster 884b is then retracted, and the wheelchair 305 is moved forward so that the back is supported by the back support wheels 810 on the step.

Referring to Figures 10a, 10b and 10c there is shown a further embodiment of a base of the wheelchair 305 and moveable support frame 325. The support frame 325 may be similar to the moveable support frames described above. In this embodiment, the wheelchair 305 comprises a base frame 1010 that supports a width adjustment means 1015. The base frame 1010 also supports a chair support means 1020 for supporting and adjusting the height of the chair 307. The base frame 1010 further supports two base rails 1035, that support the support frame 325. The width adjustment means 1015 is connected to two side frames 1040a, and 1040b. Side frame 1040a comprises a center load bearing wheel 1042a and front and rear support wheels 1044a. Side frame 1040b comprises a center load bearing wheel 1042b and front and rear support wheels 1044b.

The width adjustment means 1015 can change the distance between the two side frames 1040a, 1040b. The width can be varied between a minimum narrow width (shown in figure 10c) in which the transferring wheelchair 1005 can fit in an aisle, for example a width of 15 inches, and a maximum width (shown in figure 10b) in which greater stability is provided. The maximum width provides additional stability, making moving, for example between terminals safer.

The chair support means 1020 can adjust the height of the chair 1030 between a lowered position in which the chair is close to the ground (shown in figure 10b), and a raised position (shown in figure 10c) in which the chair is positioned above any obstructions in the transfer path, such as armrests. The lowered seat position lowers the center of gravity of the wheelchair 305 making moving, for example between terminals, safer. The raised position allows the seat to be raised above obstructions in the transfer path, making transferring to an adjacent seat easier.

Referring to Figure 11 there is shown a preferred width adjustment means 1015 and chair support 1020 that can be mounted on the base frame 1010. The width adjustment means 1015 and chair support 1020 comprise a mounting block 1101 for mounting to the base frame. Two width control arms 1103a and 1103b are pivotally connected at one end to a width control plate 1105 connected to a width positioning means 1107, The width positioning means 1107 may be for example a linear actuator for adjusting the distance between the width control plate 1105 and the front of the mounting block 1101. Each width control arm 1103a, 1103b is pivotally connected at its other end to a side frame mounting plate 1109. Each width control arm 1103a, 1103b is pivotally connected somewhere along its length to one end of a width linkage 1113a, 1113b. The other end of each width linkage 1113a,b is pivotally connected to the mounting block 1101. Varying the distance between the mounting block 1101 and the width control plate 1105 changes the distance between the two side frame mounting plates 1109. The amount the width is changed by depends on the length of the width control arms 1103a,b, the location of the pivot of the width linkage on the width control arms 1103a,b and the distance the width control plate moves. A width plate 1120, pivot arms 1121a, 1121b and side frame mounting plates 1122a, 1122b may also be mounted to mounting block 1 101 to provide a more robust mechanism for adjusting the width between the side frames 1040a,b that are connected side frame mounting plates 1122a,b, 1109a,b.

The chair support means 1020 may be mounted to the mounting block 1101 through a linkage 1130. The linkage 1130 may be controlled by a height control arm 1135 connected to a height control plate 1137 located between the front of the mounting block 1101 and the width control plate1105. When the height control plate 1137 is located adjacent the mounting block 1101 the height control arm 1135 lowers the linkage 1130 and so the height of the chair. When the height control plate 1137 is located away from the mounting block 1101 the height control arm 1135 raises the linkage 1130 and so the height of the chair.

By locating the height control plate 1137 between the mounting block 1101 and the width control plate 1105 ensures that the chair is in the lowered position when the side frames 1040a,b are in the maximum width position. When the side frames 1040a,b are at their maximum width, the width control plate 1105 is located close to the mounting block 1101, causing the height control plate 1137 to be located close to the mounting block 1101 as well, and so place the seat in the lowered position. Lifting and lowering the seat and transforming the wheel base width may be preferably performed by electric motors, or other types of actuators. However mechanical means may also be used.

Referring to Figure 12 there is shown a stability rail 1200 in accordance with the present disclosure. The stability rail1200 may be used instead of the width adjustment means 1015 described above to provide additional stability when moving. The stability rail 1200 connects to the base rail of the transferring wheelchair in a similar manner as the transfer extension rail described above. The stability rail 1200 has a wheel 1205 located apart from the base connector 1242. In addition to providing greater stability during transport, the stability rail 1200 can include a motor for assisting in moving the transferring wheelchair, Alternatively or additionally the stability rail may include a brake assist to help control the transferring wheelchair when going down a ramp or incline.

A single stability rail 1200 is shown in figure 12, however it is understood that an additional stability rail 1200 could be connected to the transferring wheelchair. The power and brake assist does not need to be part of the stability rail. It may mount to a connector on a different mounting point on the transferring wheelchair, or it may be incorporated into the base of the transferring wheel chair.

It may be seen from the above that the present wheelchair is capable of transferring a PRM from the wheelchair to any seat in an aircraft, train, bus example with ease.

The structure of the support frame allows it to be fabricated using many different types of materials such as aluminum, carbon fiber, steel, etc. while still maintaining its stability during the transfer of a PRM.

Various changes and modifications to the components of the wheelchair are possible without departing from the scope of the invention. Components may be combined or omitted as would be apparent to one skilled in the art.

Claims

WHAT IS CLAIMED IS:

1. A wheelchair comprising: a base having at least a pair of wheels for engaging a deck surface and a chair for supporting a person with restricted mobility (PRM) on the base; and a support frame releasably coupled to the base, the support frame having: an attachment support section for positioning and carrying a connector in proximity to a supported PRM, the connector for releasably coupling to a PRM support harness; and a bearing section at a lower end of said support frame for carrying along said deck said support frame from a position on said base to a position along side said base whereat a coupled PRM may be deposited.

2. The wheelchair as claimed in claim 1, said bearing section engaging an extension rail arranged on said deck.

3. The wheelchair as claimed in claim 2, said support frame having a generally inverted

U shape and spanning said chair.

4, A wheelchair comprising: a base comprising a first base rail having a generally horizontal surface arranged along a transfer direction; and a support frame comprising: a support structure having a lower section extending to an upper section; an attachment support structure attached to the support structure at the upper section and extending at least partially over the base; a first bearing section attached to the lower section of the support structure comprising a bearing surface bearing on the generally horizontal surface of the base rail, the bearing section adapted to allow the support frame to move in the transfer direction along a transferring surface contiguous with the generally horizontal surface of the base rail.

5. The wheelchair as claimed in claim 4, further comprising a transfer harness connector adapted to be coupled to the support frame.

6. The wheelchair as claimed in claim 5, wherein the base ftuther comprises: a chair coupled to the base; and a wheel coupled to the base to allow the wheelchair to be moved down an aisle of a fixed width; wherein the attachment support structure extends at least partially over the chair and the transfer harness connector is coupled to the attachment support structure above the chair.

7. The wheelchair as claimed in any one of claims 4 to 6, wherein the support structure of the support frame comprise: a first vertical support section comprising the upper section and the lower section; and a second vertical support section connected to the first vertical support section by the attachment support structure, and connected to a second bearing section having a bearing surface bearing against a second generally horizontal surface; wherein the first vertical support section of the support structure is located towards the front of the base and the second vertical support section of the support structure is located towards the back of the base, the first vertical support section, the attachment support section and the second vertical support section forming an arch extending over the base.

8. The wheelchair as claimed in claim 7, further comprising: a second base rail having a generally horizontal surface arranged parallel to the first base rail; wherein the second generally horizontal surface that the second bearing section bears on is the generally horizontal surface of the second base rail; and wherein the first base rail is located towards the front of the base and the second base rail is located towards the rear of the base.

9. The wheelchair as claimed in any one of claims 4 to 8, wherein the first bearing section comprises one of: a bushing; or a roller bearing having a rolling section comprising a cylinder having a first diameter for bearing on the horizontal surface of the first base rail and an expanded annular section having a second diameter larger than the first diameter on each end of the cylinder, the expanded annular guiding the bearing section along the generally horizontal surface of the first base rail in the transfer direction.

10. The wheelchair as claimed in any one of claims 6 to 9 when dependent upon claim 6, wherein the second bearing section comprises one of; a bushing; or a roller bearing having a rolling section comprising a cylinder having a first diameter for bearing on the horizontal surface of the second base rail and an expanded annular section having a second diameter larger than the first diameter on each end of the cylinder, the expanded annular guiding the bearing section along the generally horizontal surface of the second base rail in the transfer direction.

11. The wheelchair as claimed in any one of claims 4 to 10, wherein the first bearing section comprises: a first side arranged on a first side of the bearing surface; a second side arranged on a second side of the bearing surface; and a rail capture device arranged adjacent the generally horizontal surface of the base rail and opposite the bearing surface of the first bearing section with the generally horizontal surface arranged between the rail capture device and the bearing surface.

12. The wheelchair as claimed in any one of claims 5 to 11, when dependent upon claim 5, wherein the transfer harness connector is coupled to the support frame by a transferring system comprising: a cable having one end connected to the transfer harness connector; and a motor connected to the support frame, the motor coupled to an other end of the cable; wherein the cable passes through a guide in the attachment support structure located above the base.

13. The wheelchair as claimed in any one of claims 4 to 12, wherein the base comprises: a base frame comprising a longitudinal member; a first side frame having a wheel; a second side frame having a wheel; a width control means connected to the base frame for adjusting the width of the base by varying the distance between the first side frame and the second side frame; and a chair control means connected to the base frame for adjusting the height of a chair coupled to the base.

14. The wheelchair as claimed in claim 13, wherein the width control means comprises: a mounting block for connecting the width control means to the base frame; a width control plate having a first width control arm having a first end pivotally connected on a first side of the width control plate and a second width control arm having a first end pivotally connected to a second side of the width control plate; a first side frame mounting plate pivotally connected to a second end of the first width control arm adapted to be secured to the first side frame; a second side frame mounting plate pivotally connected to a second end of the second width control arm adapted to be secured to the second side frame; a first width control linkage pivotally connected to the first width control arm between the first end and second end of the first width control arm, an other end of the first width control linkage pivotally connected to the mounting block; a second width control linkage pivotally connected to the second width control arm between the first end and second end of the second width control arm, an other end of the second width control linkage pivotally connected to the mounting block; and an actuator mounted to the mounting block adapted to change the distance between the width control plate and the mounting block, thereby causing the distance between the first side frame mounting plate and the second side frame mounting plate to change.

15. The wheelchair as claimed in claim 13, wherein the chair control means comprises; a height control plate located between the mounting block and the width control plate; an actuator mounted to the mounting block adapted to change the distance between the height control plate and the mounting plate; a height linkage arm having a first end pivotally connected to the top of the mounting block and a second end pivotally coupled to the chair; and a height control arm having a first end pivotally connected to the height control plate and a second end pivotally connected to the height linkage arm between the first end and the second end.

16. The wheelchair as claimed in any one of claims 4 to 15, wherein the base comprises a stepping means adapted to allow the wheelchair to travel over a step, the stepping system comprises: a first stepper located in front of a center wheel approximately located at the longitudinal center of the base frame, the first stepper comprising; a first height adjustment means connected to the base and a first stepper wheel, the first height adjustment means adapted to raise or lower the stepper wheel above or below the plane of the center wheel; and a second stepper located opposite the first stepper, the center wheel located between the first stepper and the second stepper the second stepper comprising: a second height adjustment means connected to the base and a second stepper wheel, the second height adjustment means adapted to raise or lower the second stepper wheel above or below the plane of the center wheel.

17. A wheelchair transferring system for people with restricted mobility comprising: the wheelchair as claimed in any one of claims 4 to 16; and an extension rail having a generally horizontal surface, releasably attached to the base rail so that the horizontal surface of the base rail and the horizontal surface of the extension rail form a contiguous horizontal surface, the support frame on the contiguous horizontal surface between a transport position in which the transfer harness connector of the support frame is located above the base and a transfer position in which the transfer harness connector of the support frame is located above a seat located laterally adjacent the base.

18. The wheelchair transferring system as claimed in claim 17, wherein the extension rail further comprises a locking means for securing the extension rail to the wheelchair.

19. The wheelchair transferring system as claimed in claim 17 or 18, further comprising a foot located at an end of the extension rail opposite the wheelchair, the foot adapted to raise the generally horizontal surface off the ground and stop the lateral movement of the support frame on the generally horizontal surface.

20. A method of transferring a person with restricted mobility from a transferring wheelchair as claimed in one of claims 4 to 17 to a seat, the method comprising the steps of: moving the wheelchair to a location adjacent the seat; securing the person with restricted mobility to the support frame; locating an extension rail having a generally horizontal surface in front of or behind the seat and adjacent the wheelchair to form a contiguous surface with the generally horizontal surface of the base rail of the transferring wheel chair; moving the support frame on the contiguous surface from a first location located above the base of the wheelchair, to a second location above the seat located adjacent the transferring wheel chair; and un-securing the person with restricted mobility from the support frame thereby transferring them to the seat.