Personal mobility vehicle with tiltable seat

ES 2 389 730 T3

DESCRIPTION

Personal mobility vehicle with an adjustable seat.

Background of the invention

The present invention relates, in general, to land vehicles and, more particularly, to personal mobility vehicles. More particularly, the invention relates to a personal mobility vehicle having a reclining seat assembly according to the preamble of claim 1.

Personal mobility vehicles with reclining seats are well known. Such vehicles are typically used in geriatric or highly dependent care, where the ability to reposition a vehicle occupant in various angular positions is beneficial to occupant health and daily routine. Tilting a vehicle occupant relieves pressure on the vehicle occupant's ischial tuberosities (ie, the bony prominence of the buttocks). Continuous pressure on the ischial tuberosities of the vehicle occupant, which is applied when the vehicle occupant remains in a single sitting position, can cause the development of pressure sores (ie, pressure sores). For vehicle occupants with severe kyphosis (ie, curvature of the spine), sitting at an incline can allow the occupant to look ahead and interact with their surroundings. Leaning can also be beneficial to aid proper breathing and digestion.

Some occupants of personal motor vehicles require a personal care assistant, in which an assistant is responsible for positioning the angle of the vehicle seat, frequently changing the angle on a prescribed schedule. The ability to tilt the vehicle occupant offers the occupant a variety of positions that facilitate their daily planning, including, for example, a forward tilt to eat at a table and a backward tilt to rest.

Conventional tilting personal mobility vehicles consist of a seat frame that is pivotally mounted to a base frame such that the seat frame tilts to reposition the occupant of the vehicle. The pivot shaft is typically mounted between the base frame and the seat frame, toward the rear of the seat and away from the occupant's center of gravity. Tilting the occupant involves raising or lowering their center of gravity and therefore requires effort on the part of the attendant. Mechanisms, such as springs or gas cylinders, are often used to help tilt the occupant. Typically, there are levers attached to the handles on a tilt-seat vehicle. The levers allow an assistant to release a locking mechanism, change the tilt angle by pushing or pulling the handles, and engage the locking mechanism that sets the tilt angle.

The seat tilt in conventional tilting personal motor vehicles can generate a reaction from the occupant, who experiences a tipping sensation. The occupant experiences a sensation of loss of balance during the incline. Conventional tilt seat designs involve a shift in the vehicle's occupant's center of gravity during tilting. Considerable effort may be required on the part of the attendant to tilt the vehicle occupant when the mass of the occupant is displaced during the tilt. Additionally, conventional vehicles with tilt seats require large base frames and anti-tip devices, as the seat tilt shifts the occupant's center of gravity forward and backward over the wheelbase, which could cause the vehicle to lose balance. .

Document CA 2 546 741 A1 discloses a wheelchair comprising a tilting seat. The seat is operatively connected to a wheelchair frame by an arch support member and by a gear rack such that, as the seat is tilted, the center of gravity of a person sitting in the wheelchair wheels are substantially maintained. The wheelchair may also contain a reclining seat back member.

What is needed is a personal mobility vehicle that does not create the sensation of overturning; that requires minimal effort on the part of the assistant to tilt (that is, without the need to raise or lower the center of gravity of the vehicle occupant to tilt the vehicle seat assembly); that does not affect the weight distribution between the front and rear wheels, and that is limited to pure rotation (i.e. the only effort required is to overcome friction in the system), thus eliminating the need springs or gas cylinders to facilitate tilting.

Summary of the invention

The present invention is directed to a personal mobility vehicle that overcomes the above deficiencies, and which is defined in claim 1.

ES 2 389 730 T3

An embodiment of the invention is directed to a personal mobility vehicle comprising a personal mobility vehicle having a seat that allows movement relative to a radial or near radial curve, having a center of curvature that is preferably substantially fixed in space. The seat is adjustable with respect to the curve so that the center of gravity of an occupant of the vehicle is sufficiently coincident with the focal point of the curve so that the force required to tilt the seat is minimized.

Another embodiment of the invention is directed to a personal mobility vehicle comprising a base and a seat to support an occupant of the vehicle. The seat allows movement along a curve that has a center of curvature. The seat is adapted to support a vehicle occupant having a center of gravity that is adapted to be positioned relative to the center of curvature sufficient to minimize the effort required to move the seat, with the vehicle occupant in it, throughout. along the curve.

Another embodiment of the invention is directed to a personal mobility vehicle comprising a base, a plurality of wheels that are adapted to support the base with respect to a supporting surface, and a seat to support an occupant. The seat is supported relative to the base for movement along an arcuate path with a fixed center of rotation. The seat is adjustable so that the occupant's center of gravity is adapted to be substantially coincident with the center of rotation.

Another embodiment of the invention is directed to a personal mobility vehicle comprising a base, a plurality of wheels that are adapted to support the base with respect to a supporting surface, a seat, one or more rails, having an arch of constant radius, which support the seat for movement relative to the base, and a low friction support assembly supported by the base or the seat or any combination thereof. The bracket allows adjustment of a range of global tilt angles of the one or more rails.

Another embodiment of the invention is directed to a personal mobility vehicle comprising a base, a plurality of wheels that are adapted to support the base relative to a supporting surface, a seat to support an occupant, and one or more rails that support the seat. The rails serve as a running or sliding surface that allow the seat to rotate relative to the base. The rails have an arc of constant or substantially constant radius with a focal point that is substantially fixed in space, so that the location of the occupant's center of gravity can be adjusted to be coincident or nearly coincident with the focal point.

The personal mobility vehicle allows a method to minimize the effort required to tilt the seat of a personal mobility vehicle. The method comprises the steps of providing a personal mobility vehicle having a seat that is adapted to move along an arc having a center of curvature, positioning the seat substantially horizontally, providing an occupant in the seat, and adjusting the position of the vehicle occupant's center of gravity so that the center of gravity is substantially the same or is below the center of curvature of the arch.

Various objects and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of the preferred embodiment, with reference to the accompanying drawings.

Brief description of the drawings

Fig. 1 is a front perspective view of a personal mobility vehicle according to a preferred embodiment of the invention.

Fig. 2 is a side elevation view of the vehicle shown in Fig. 1.

Fig. 3 is a front perspective view of a base frame and a vehicle seat frame with an alternative backrest.

Fig. 4 is a bottom, rear perspective view of the base frame and seat frame shown in Fig. 3.

Fig. 5 is a side elevational view of a base frame and seat frame with graphic designations indicating directional movement of a rocker bracket and axle mounting plate.

FIG. 6 is a partial side elevational view of the vehicle with graphic designations indicating the focal point of the arc of a rocker, which is substantially coincident with the center of gravity of a vehicle occupant, and the weight distribution of the vehicle. occupant to a supporting surface.

FIG. 7 is a partial side elevational view of the vehicle with graphic designations indicating the directional movement of a footrest and seat back bar assembly.

ES 2 389 730 T3

Fig. 8 is an enlarged perspective front view of a coupling for securing the seat back to the seat frame.

Fig. 9 is a partial side elevational view of the vehicle with graphic designations indicating an adjustment in the angle of the rocker bracket.

FIG. 10 is a sectional view, on an enlarged scale, in elevation, of a lock assembly for locking the rocker arm relative to the rocker arm bracket.

FIG. 11 is an enlarged sectional elevation view of an alternative lock assembly.

Fig. 12 is a front perspective view, on a reduced scale, of a vehicle according to an alternative embodiment of the invention with handle assemblies that allow the control and movement of the seat frame by the vehicle occupant.

Fig. 13 is a sectional view, on an enlarged scale, in elevation, of the base frame, the rocker support and the rocker.

<td>Figs. 14A and 14B are front views and folding seat configuration.</td><td>side,</td><td>partial,</td><td>on</td><td>raised,</td><td>to scale</td><td>reduced,</td><td>vehicle</td><td>with a</td>

<td>Figs. 15A and 15B are front views and standard seat configuration.</td><td>side,</td><td>partial,</td><td>on</td><td>raised,</td><td>to scale</td><td>reduced,</td><td>vehicle</td><td>with a</td>

<td colspan="5">Figs. 16A and 16B are partial front and side elevational views, standard seat configuration with spacers that raise the seat.</td><td>to scale</td><td>reduced,</td><td>vehicle</td><td>with a</td>

<td>Figs. 17A and 17B are front views and</td><td>side,</td><td>partial,</td><td>on</td><td>raised,</td><td>to scale</td><td>reduced,</td><td>vehicle</td><td>with a</td>

standard seat configuration with spacers that raise the seat and a cushion supported by the seat.

Figs. 18A and 18B are partial, side elevational, reduced-scale views of the vehicle with the base frame in the up and down positions.

Figs. 19A and 19B are partial views, in side elevation, on a reduced scale, of alternative means for removing the seat.

Figs. 20A and 20B are schematic views depicting the vehicle with the seat frame positioned so that the center of gravity of the vehicle occupant is over the focal point of the arc of a rocker.

Figs. 21A and 21B are schematic views depicting the vehicle with the seat frame positioned so that the center of gravity of the vehicle occupant is below the focal point of the arc of a rocker.

Fig. 22 is a schematic view showing the vehicle with the seat frame positioned such that the center of gravity of the vehicle occupant is substantially coincident with the focal point of the bow of a rocker.

Detailed description

Referring now to the drawings, in Figs. 1 and 2 illustrate a personal mobility vehicle, generally indicated 10. Vehicle 10 has a base 12 and a seat assembly 14 supported by base 12. Base 12 is supported on a supporting surface by wheels, such as the front caster wheels 16 and the rear wheels 18 shown. The front wheels 16 are preferably caster wheels, and the rear wheels 18 are preferably driven wheels, which can be manually driven or power driven. Note that the shown motorized personal vehicle is in the form of a wheelchair, but the invention is intended to be practiced with other personal mobility vehicles, including but not limited to scooters. Although the illustrated wheelchair is a rear wheel drive chair, the invention can be practiced with middle front wheel drive vehicles. The seat assembly 14 has a seat frame 20 and a seat back 22. Seat frame 20 includes longitudinally extending frame members, such as tubes, to support a seat 24, which may be in the form of a rigid or semi-rigid tray, as shown, or an elastic or flexible sling (not shown ). Seat 24 may include adjustable portions, such as the telescopic portions shown, that are longitudinally adjustable, relative to one another, to allow adjustment of the length of seat 24. Seat back 22 preferably includes laterally spaced bars 26 to support a back (not shown). The bars 26 are preferably formed of adjustable parts, such as the telescopic tubes shown, which allow the length of the bars 26 and the seat back 22 to be adjusted. A 28 handle can

ES 2 389 730 T3 be supported by the bars 26. In the illustrated embodiment, the handle 28 is rotatably coupled to the bars 26, preferably by couplings 30 which are adapted to removably hold the handle 28 in a fixed relationship to bars 26.

Seat frame 20 is preferably adapted to support armrests 32 and footrest assemblies 34. The armrests 32 are preferably removably attached to the seat frame 20 and are movable in a longitudinal direction relative to the seat frame 20. Armrests 32 are preferably maintained in a fixed relationship relative to seat frame 20 in any conventional manner, such as by tube clamps 36 shown. The footrest assemblies 34 are also removably and movably attached to the seat frame 20.

As illustrated in Figs. 3 and 4, base 12 includes a base frame (shown but not referenced), which is comprised of opposing side frame members, such as tubes 40, joined by a pair of longitudinally spaced, laterally extending frame members, such as like tubes 42 shown. It should be noted that the tubes 42, which extend laterally, are preferably telescopic tubes that are adjustable, relative to one another, to allow the vehicle 10 to increase in width. It should further be noted that the position of the laterally extending tubes 42 is preferably adjusted relative to the side tubes 40, for example, by means of the longitudinally spaced holes and clips (not shown).

The seat frame 20 is similarly composed of opposite side frame members, such as tubes 44 shown, and curved or substantially curved members, such as rails or rocker arms 46 shown, or a curved rack (not shown). , joined by a plurality of longitudinally spaced, laterally extending members, such as tubes 48 shown. It should be noted that the laterally extending tubes 48 are preferably in the form of telescopic tubes that can be adjusted together to allow the vehicle 10 to increase in width. The seat frame 20 is supported relative to the side tubes 40 by the rocker arms 46 by means of one or more support assemblies 50.

As shown in the view, the side tubes 40 can support caster wheel housings 52, which in turn are suitable for supporting the caster wheel stems. The rear wheels 18 may be supported in a fixed relationship to the side tubes 40 by any conventional means, including the axle mounting plate 54 shown.

Footrest assemblies 34 may include a member, such as tube 56, that is telescopically received by, or if not adjustably related to, side tubes 44. Tube 56 is preferably adjustable relative to side tubes 44 to allow the longitudinal position of tube 56 to be located at various fixed positions relative to side tubes 44. This allows growth in vehicle 10 in a longitudinal direction.

It should be noted that an alternative seat back 58 is shown in Figs. 3 and 4, wherein the opposite handles 60 are provided on opposite bars 62. Handles 60 may be telescopically received at, or otherwise adjustable relative to, bars 62. A further assistive handle 64 may optionally extend rearward from bars 62.

As shown in Fig. 5, the support assemblies 50 and the axle mounting plates 54, preferably adjustable in a longitudinal direction. This can be achieved in any suitable way. For example, in the illustrated embodiment, the side tubes 40 may be provided with a series of longitudinally spaced holes 66. Each of the support assemblies 50 and axle mounting plates 54 may be provided with holes 116, 117 and 72, which are spaced apart to align with holes 66 in the side tubes 40. Fixing elements (not shown) may be adapted to be secured in aligned holes to maintain support assemblies 50 and axle mounting plates 54 in substantially fixed relationship to side tubes 40. To move the support assemblies 50 and shaft mounting plates 54, simply remove the screws. Support assemblies 50 and axle mounting plates 54 can move longitudinally (ie, in the left and right directions when looking at Fig. 5). This allows the weight, as represented by W in Fig. 6, the vehicle occupant is adjusted longitudinally with respect to the wheelbase, for example, to optimize performance and steering stability. A preferred weight distribution is about 40 percent on the front caster wheels 16 and 60 percent on the rear wheels 18. Such an adjustment also allows the wheelbase to grow lengthwise, for example, to accommodate occupants of varying size.

Continuing with Fig. 6, arc A preferably has a radius R that is constant or substantially constant. The center of curvature or focal point P of arc A is preferably coincident with the center of gravity CG of the vehicle occupant. The constant radius arc A and the coincident focal point P and the center of gravity CG are preferred such that the center of gravity CG remains fixed or substantially fixed as the set 14

ES 2 389 730 T3 seat is inclined (that is, as the seat assembly 14 is displaced clockwise and counterclockwise when looking at Fig. 6).

In Fig. 7, there are directional arrows (i.e., pointing left and right when looking at the drawing) that represent the movement of the footrest assemblies 34 and the backrest bars 62, for example, to allow the seat system is adjusted for occupants of different sizes. The growth capacity of these two components in two directions also allows an adjustment, so that the center of gravity of the occupant of the vehicle remains at the center of rotation or focal point P. This can be achieved in any suitable way. For example, the tubes 56 of the footrest assemblies 34 may be telescopically received by, or if they cannot be adjusted relative to, the side tubes 44 and bars 62 may have couplings 74 or other suitable members that may be attached for relative movement. to the side tubes 44. The tubes 56 and couplings 74 may have holes, which are adapted to align with the holes in the side tubes 44 of the seat frame 20, and fasteners (not shown) can be adapted to, and secured in, the holes.

Couplings 74 are preferably structured to be adjustable with minimal disassembly. As shown in FIG. 8, the couplings 74 may include a set of plates 80 and clamping clamps 82, 84. The upper ends of the plates 80 may be attached to the bottom of the bars 62 by bar holding clamps 82. The holes 86, 88 in the plates 80 and the clamping clamps 82 can be aligned with the holes (not shown) in the bars 62 to receive a clamping element 90. This clamping element 90 can form a pivot so that the bars 62 fold down in the direction D relative to the side tubes 44 of the seat frame 20. Each plate 80 may have another hole 92 just below the bottom of the bar 62. These plate holes 92 can be aligned with each other to receive another fastener 94. This clamping element 94 can be selectively engaged and disengaged by a piston 96 which is biased downward by a spring 98. A lever 100 or other suitable control member, which extends rearwardly from the piston 96, may be movable to lift piston 96 out of engagement with clamp 94 to allow rods 62 to fold downward. The lower ends of the plates 80 can be attached to the side tubes 44 of the seat frame 20 by means of the opposite elongated clamping clamps 84. The lower ends of the plates 80 and elongated clamping clamps 84 may have alignment holes 102, 103 and 104, 105 to receive the clamping elements 106, 108 for securing the plates 80 and elongated clamping clamps 84 to the tubes. 44 sides of the seat frame 20. It should be noted that the elongated clamping clamps 84 have protrusions 110 extending laterally therefrom. The protrusions 110 are mating with the rear holes 103 in the clamping brackets 84. The rear holes 105 of the plates 80 are preferably sized to receive the protrusions 110. The upper fasteners 90, 94 hold the plates 80 together with the protrusions 110 in the holes 105. The protrusions 110 function as a pivot to adjust the angle (eg, recline angle) of the bars 62 relative to the side tubes 44 of the base frame 20. The lower clamp members 106, 108 are preferably removable to allow the plates 80 and elongated clamp brackets 84, together with the bars 62, to move longitudinally relative to the side tubes 44 of the seat frame 20.

As clearly illustrated, the holes 102, 103 in the elongated clamping brackets 84 are adapted to align with the holes 111 in the side tubes 44 of the seat frame 20. The fastening elements 106, 108 may be received in any of the aligned holes, for example, to accommodate growth in the vehicle 10 in a longitudinal direction and to allow a wide range or variation in the positions of the footrest assemblies 34 and the assemblies. 50 support to allow the occupant of the vehicle to be positioned with its center of gravity CG substantially coincident with the arc A of the focal point P.

Also illustrated in FIG. 8 are tabs 112 extending downwardly from elongated clamping clips 84. The tabs 112 have holes 114 extending laterally therethrough. Front holes 102 in elongated clamping brackets 84 and holes 114 in tabs 112 align with holes 104, which preferably form an arcuate arrangement of scalloped holes, in plates 80. The rear hole 105 in each plate 80 is preferably the focal point of the arcuate arrangement. The lower front fastener 106 is adapted to be received through the front holes 102 in the elongated fastening clamps 80 or the holes 114 in the tabs 112 and through any one of the scalloped holes 104. Alternatively, the lower front fastener 106 is adapted to be received through the front hole 102 in the elongated clamps 80, and an optional additional fastener (not shown) is adapted to be received through the holes 119 in the tabs 112 and through another of the scalloped holes 104. This allows the angle of the bars 62 to be adjusted relative to the side tubes 44 of the seat frame 20 to recline the bars 62.

The functionality of the coupling 74 is a result of the use of elongated clamping clamps 84. These clamping clamps 84 allow for angular and longitudinal adjustment of the bars 62 and plates 80 more easily than conventional coupling systems that perform a similar function. Both for setting 6

ES 2 389 730 T3 angular as for longitudinal adjustment, the upper clamping elements 90, 94 remain intact with the plates 80 and clamping clamps 82.

Angular adjustment of the bar 62 and plates 80 relative to the seat tube 44 of the illustrated coupling 74 can be achieved by removing the lower front clamp 106 and accommodating the rear lower clamp 108 to reduce the clamping pressure of the plates. 80 over the clamping clamps 84 and the side tubes 44. The bars 62 and plates 80 are then free to rotate, coincidentally, around the holes 105 in the back plate and the holes 103 in the rear clamp.

Longitudinal adjustment of the bars 62 and plates 80 of the illustrated coupling 74 can be achieved by removing only the lower front and rear fasteners 106, 108. There are no other parts that need to be removed or that may loosen or come loose during this adjustment as the lower rear holes 105 in the plates 80 mate, coincidentally, around the protrusions 110 of the clamping clamps 84 and the plates 80. maintain a pre-load against the clamping clamps 84 and the lateral tube 44 due to the installed clamping force of the upper clamping elements 90, 94, such that the plates 80 remain engaged with the clamping clamps 84. When the desired longitudinal location of the bars 62 is established along the side tube 44, the lower front and rear fasteners 106, 108 can be re-installed and secured in place.

It should be noted that, during longitudinal adjustments, the preset angular adjustments of the bars 62 and plates 80 can be preserved by first removing the rear fastener 108 from the holes 103, 105 in the fastening clamps 84 and the plates 80 and then placing the rear fastener 108 completely through the holes 114 in the tabs 114 of the fastening clamps and the scalloped holes 104 in the plates 80. The rear fastener 108 is now in a shear mode that maintains the angular position of bar 62 and plates 80. Next, by removing the lower front clamp 106, the entire assembly (ie, bar 62 and plates 80) is free to move longitudinally along side tube 44.

An example of a structure for adjusting the angle of rocker arms 46 is illustrated in Fig. 9. It should be appreciated that the structure is provided for illustrative purposes, and that other structures could be used to carry out the invention. The structure shown is supported by the support assemblies 50. The support assemblies 50 may include one or more side plates 115, each having a first mounting hole 116 therein, and a plurality of angle adjustment holes 117a, 117b, 117c, spaced apart, at a separate relationship with the first mounting hole 116. The first mounting hole 116, in combination with one of the angle adjustment holes 117a, 117b, 117c, supports the seat assembly 14 at a fixed or substantially fixed angle relative to the base 12 and relative to the other holes 117a. , 117b, 117c of angle adjustment. For example, the first mounting hole 116 and a first hole among the angle adjustment holes 117a support the bracket assembly 50 at an angle α, which is approximately zero degrees relative to the side tubes 40, although these may be desired. other angles. The first mounting hole 116 and a second hole among the angle adjustment holes 117b support the bracket assembly 50 at an angle β, which is approximately five degrees relative to the side tubes 40. Although another angle may be desired. The first mounting hole 116 and a third hole of the angle adjustment holes 117c support the low friction support assembly 50 at an angle γ, which is approximately ten degrees relative to the side tubes 40. It should be clearly understood that these three angle adjustments affect the tilt range of the seat assembly 14. It should be understood that the 0, 5 and 10 degree angle settings shown are provided for illustrative purposes and that the invention can be practiced with other suitable angle settings.

In FIG. 10, a lock assembly 130 is illustrated for locking rocker arms 46 relative to one or more support assemblies 50. Lock assembly 130 may be supported by inner plate 115 and may include a protrusion that engages one of the plurality of recesses in rocker arms 46. In the illustrated embodiment, a plunger pin 132 may be displaced by a spring 134 to engage one of a plurality of holes 136 in the rocker arms 46. The plunger pin 132 and spring 134 may be housed in a housing 138 which is threaded, pressed or otherwise held in a fixed relationship with a hole in the inner plate 115 of the support assemblies 50. Plunger pin 132 can be actuated by cable 140, which can be controlled by a conventional lever (eg, levers 154 shown in Fig. 12). The lever may be supported on one of the handles 60 of the seat back 58 to allow the plunger 132 to be actuated by an assistant.

An alternative lock assembly 142 is illustrated in Fig. 11. This lock assembly 142 would be suitable for use with a rail, such as the rocker 144 shown, having a round, tubular cross section. Lock assembly 142 may include a pair of lock plates 146 that are held in spaced relationship by spring 148. Spring 148 may be secured for movement relative to side plate 115 of one or more of the assemblies. 50 support. Spring 148 is adapted to move lock plates 146 outwardly by

ES 2 389 730 T3 opposite directions (that is, in the left and right directions when looking at Fig. 10) and in engagement with rocker tube 144 to prevent rocker tube 144 from moving relative to plates 146 lock. Note that a drive cable 150 can extend through the lock plates 146 and can control the lock plates 146 to disengage the lock plates 146 from the rocker tube 144 to allow the rocker tube 144 to move.

In Fig. 12, a vehicle is illustrated having handles 152 with support levers 154 to actuate cables to control rocker lock assemblies, such as the lock assemblies described above. The handles 152 may also be provided with handles 156 to allow the vehicle occupant to lean on the seat assembly 14 relative to the base 12.

In FIG. 13, there is illustrated a cross-sectional view of a side tube 40 of the base 12, a rocker 46 of the seat assembly 14, and a support assembly 50 that supports the rocker 46 relative to the side tube 40. According to the illustrated embodiment, the side tube 40 of the base 12 is located between the side plates 115 of the support assembly 50. As noted above, the side plates 115 can be attached to the side tube 40 by fasteners, such as the bolt 160 shown, which passes through holes 66 (also shown in Fig. 5) in the tube. 40 that align with the corresponding holes in the side plates 115. A lower roller 162 may be supported for movement on the side tubes 40 by a shaft 164. The lower roll 162 may be supported in spaced relationship to the side tubes 40. Rocker 46 may have a contact surface 166 that engages lower roller 162. Rocker 46 and lower roller 162 preferably have mating surfaces, such as rounded contact surface 166 of rocker arms 46 and saddle-shaped surface 167 of lower roller surface 162. Rocker 46 may further have an arcuate relief 168 on one side thereof. The arc of relief 168 preferably has a radius that is constant or substantially constant. An upper roller 170 preferably engages the relief 168 to trap a portion of the rocker 46 against the lower roller 162. The upper roller 170 is preferably supported by an adjustable eccentric cam bolt 172. It should be appreciated that the relief 168 and upper roll 170 may include mating surfaces that engage each other with a force that is dependent on the position of the eccentric cam bolt 172. It should be appreciated that the present invention is not intended to be limited to rocker 46 and rollers 162 170, discussed above, but can be practiced with other low-friction elements, such as, but not limited to, one or more bearings, ramps, pinion skates, and / or or similar.

As shown in Figs. 14A to 17B, the seat assembly 14 is adapted to support a variety of seats. For example, the seat 174 illustrated in Figs. 14A and 14B is a folding seat, which is adapted to be supported under the side tubes 44 of the seat frame 20, so that the height H1 of the seat 174 is minimized. The seat 176 illustrated in Figs. 15A and 15B is a standard seat, which is adapted to be supported on the side tubes 44 of the seat frame 20, such that the height H2 of the seat 176 is substantially the same as the height of the side tubes 44. The seat 176 illustrated in Figs. 16A and 16B is a standard seat, which is adapted to be supported on the side tubes 44 of the seat frame 20 by means of spacers 178 to raise the side tubes 40 and the seat 176 to a greater height H3. It should be apparent that the height H3 depends on the size and number of spacers 178 used. The seat 176 illustrated in Figs. 17A and 17B is a standard seat similar to that shown in Figs. 16A and 16B, which further supports a cushion 180, which is raised to a greater height H4 on the side tubes 44. The seats 174, 176 noted above and the spacers 178 are adapted to be attached in any suitable manner. These and other seats may be supported by the seat assembly 14. The importance of the height adjustments, noted above, of the seat is that they allow the vertical positioning of the occupant's center of gravity to be coincident or substantially coincident with the center of curvature or focal point P of the rocker 46.

In Figs. 18A and 18B, means for adjusting the height of caster wheel housings 52 are illustrated by way of example. The adjustment means may be any suitable adjustment means including, but not limited to, an offset 182, as shown at the front end of the side tubes 40 of the base 12. As shown in FIG. 18A, the offset 182 may be directed upward to minimize the height H1 of the seat assembly 14. In Fig. 18B, the offset 182 can be directed downward to maximize the height H2 of the seat assembly 14. Also note the change in the position of the shaft sleeve 184 with respect to the side tubes 40 of the base 12 in the two drawings. The close proximity of the shaft sleeve 184 to the side tubes 40 reduces the rear of the seat assembly 14. The reverse is true if the shaft sleeve 184 is displaced downward and away from the side tubes 40. That is, the rear of the seat assembly 14 is raised accordingly. The shaft sleeve 184 can be positioned over the side tubes 40 to further reduce the rear of the seat assembly 14.

As illustrated in Figs. 19A and 19B, it is preferred that the seat assembly 14 is removed from the base 12. This can be accomplished in any suitable manner. For example, the support assemblies 50 may be removably attached (i.e. preferably easily removable with or without the aid of tools) to the side tubes 40 of the base 12, as shown in Fig. 19A. , so the support assemblies 50 and, of this, 8

ES 2 389 730 T3 way, the seat assembly 14, can be easily removed from the base 12 to facilitate the transport of the vehicle

10. Alternatively, the seat assembly 14 may be removably attached to the support assemblies 50, as shown in FIG. 19B, so that the seat assembly 14 can be easily removed from the support assemblies 50. A person of ordinary skill in the art of the invention, without undue experimentation, could provide suitable means for removably securing the seat assembly 14, including a variety of quick release fasteners.

It should be noted that the vehicle 10 can be composed of two main parts: the base 12 and the seat assembly 14. Seat assembly 14 may include seat frame 20, seat back 22, 58, and footrest assembly 34, all supported rigidly or substantially rigidly on rocker arms 46. The support assemblies 50 can capture the rocker arms 46 and restrict the movement of the seat frame 20 for pure rotation about the center of curvature of the rocker (ie, the focal point P).

In a preferred embodiment, four lower rollers 162 (ie, two rollers 162 for each rocker 46) preferably support the bottom surface of rocker arms 46. These rollers 162 are preferably saddle-shaped, to position rocker arms 46 to along the center of the support assembly 50. Rocker arms 46 preferably have a similarly shaped profile that fits within saddle-shaped rollers 162. These mating shapes serve to align rocker arms 46 with rollers 162.

Four upper rollers 170 (i.e., two upper rollers 170 for each rocker 46) preferably contact an upper curved surface of rocker arms 46, capturing rocker arms 46 and preventing rocker arms 46 from being lifted from base 12. Upper and lower rollers 162, 170 allow the seat frame 20 to rotate with minimal friction around the center P of curvature of the rocker arms 46.

It should be further noted that the holes 136, which serve as mating features for the pins 132 of spring-loaded plunger 132, may be homogeneously spaced and arranged in a series, for example, between the upper and lower surfaces of the rocker arms 46, to along an arc concentric or substantially concentric with the curvature of the rocker arms 46. The holes 136 may be spaced at discrete angular distances, such as a one degree apart, to allow for incremental adjustments in the angle of inclination of the seat frame 20. Multiple pins 132 could engage multiple holes 136 in rocker arms 46 to reduce shear forces encountered by pins 132 in locking rocker arm 46 in position. It should be clearly understood that the angle of inclination of the seat frame 20 can be changed, for example, by squeezing the levers to release the pins 132 from the holes 136 and rotating the seat frame 20 by pushing or pulling the handles. When the levers are released, the pins 132 can engage with the closest aligned holes 136, locking the seat frame 20 with respect to the base 12 at a specific angle of inclination.

For vehicle 10 to function as intended, the center of gravity of a vehicle occupant should closely coincide with the center of curvature of the rocker arms. For this purpose, the occupant of the vehicle should be positioned correctly at the center of curvature or substantially near the center of curvature of the rocker arms. For example, the vehicle occupant's center of gravity may be above the center of curvature or the focal point of the rocker (i.e., when the seat frame is substantially horizontal, as shown in Fig. 20A), although placing the vehicle occupant's center of gravity well above the center of curvature could create an inverted pendulum effect, which could create an unbalanced load, causing the seat frame to tend to rotate away from horizontal. , which may require substantial force to counteract when the seat frame is moved or tilted. This phenomenon is illustrated in Figs. 20A and 20B. The center of gravity of the vehicle occupant may also be below the center of curvature of the rocker (ie, when the seat structure is substantially horizontal, as shown in Fig. 21A). Although this is generally more suitable than when over the center of curvature, placing the vehicle occupant's center of gravity too below the center of curvature could create a pendulum effect, potentially causing the seat frame to tilt. rotate horizontally, which may also require substantial force to counteract when the seat frame is moved or tilted. This phenomenon is illustrated in Figs. 21A and 21B. In the most preferred embodiment of the invention, the center of gravity of the vehicle occupant is coincident or substantially coincident with the center of curvature of the rocker, as shown in Fig. 22. This is the most suitable relationship because the The seat system is in balance or substantially in balance, thus tilting the seat frame requires little force to overcome friction.

The preferred embodiment of the invention can be summarized as a personal mobility vehicle having a seat or a seating system that is supported for movement relative to a radial curve or a quasi-radial curve (for example, by means of a member or a radially curved rail, or a substantially radially curved member or rail) having a focal point that is preferably substantially fixed in space, wherein the seat or the seating system is adjustable (for example, horizontally, vertically, or both) with respect to the curve, such that the center of gravity of any occupant of the vehicle is

ES 2 389 730 T3 sufficiently coincident with the focal point of the curve so that excessive force, or a significant amount of force, is not required to tilt the seat frame with the occupant therein. In one embodiment of the invention, the center of gravity may be sufficiently vertically aligned with the focal point when the seat or the seating system is horizontal.

Obviously, the relative position of the vehicle occupant's center of gravity and the center of curvature, or focal point, depends on the weight of the user and possibly the physical capabilities of the attendant. For example, a nearly coincident relationship between the vehicle occupant's center of gravity and the focal point P, requiring 50 pounds (23 kg) of force to tilt the seat frame and occupant, may be an appropriate relationship for some attendees. but not for others. Generally, the center of gravity is preferably within a 2.5 cm (one inch) radius around the focal point. Depending on the occupant's weight, the center of gravity may be within a 6.3 cm (2.5 inch) radius around the focal point, although this may not be suitable for occupants exceeding certain weight capacities. The center of gravity can even be within a 7.6-10 cm (three to four inch) radius around the focal point, although this may not be a possible range for very heavy occupants. With these ranges in mind, it is conceivable that the center of gravity could even be in a radius around the focal point that is in a preferred range of about four to seven percent of the front to rear length of the vehicle seat 24, or a suitable possible range of about 11 to 17 percent of the front to back length of the vehicle seat 24.

To establish a desired relationship between the vehicle occupant's center of gravity and the focal point P of the arc A, the wheelchair 10 may incorporate various means for adjusting the position of the vehicle occupant to align the occupant's CG center of gravity with or near the center of curvature of the rocker arms 46. The seat back 22, 58, the seat 24 (eg, a tray, a sling, etc.), and the footrest assemblies 34 all preferably incorporate front to back adjustability with respect to the center of curvature. The couplings that secure the bars 26, 62 and the seat 24 to the seat frame 20 preferably allow anterior to posterior adjustability. The tubes 56 supporting the footrest assemblies 34 also preferably have anterior to posterior adjustability. This adjustability allows for proper alignment of the CG center of gravity for a range of vehicle occupant sizes and adapts to occupant growth.

The center of curvature of the rockers 46 is a virtual point in space that may preferably reside near the abdomen of the occupant. Because the pivot point in this design is a virtual point in space, and not a physical pivot axis, near the abdomen, the vehicle occupant is not confined by the hardware or the structure of the vehicle that surrounds the occupant. . The absence of any vehicle structure at this location is advantageous as the seating area remains unconfined. This helps transfer the occupant in and out of the vehicle.

Proper positioning of the CG center of gravity of a vehicle occupant relative to the base 12 is important for the stability and maneuverability of the vehicle. Stability is ensured when the center of gravity CG is properly positioned between the front caster wheels 16 and the rear wheels 18 attached to the base frame 12. Greater maneuverability is achieved when the rear wheels 18 bear the majority of an occupant's weight. The reduction in weight on the front caster wheels 16 produces improved maneuverability and makes it easier to climb the front end of the vehicle when crossing thresholds. Because the vehicle 10 is intended to cover a wide range of occupant sizes, the footprint of the vehicle (ie, the distance between the caster wheels 16 and the rear wheels 18) may increase.

Vehicle 10 incorporates several unique features to maintain stability and maneuverability while accommodating a wide range of occupant sizes. The seat frame 20 can be adjusted forward and backward relative to the base 12. The seat frame 20 can be positioned relative to the base 12 by moving the support assembly 50 forward / backward along the base 12. The rear wheels 18 can also be positioned forwards / backwards along the base 12. This ability to adjust the size of the vehicle's footprint and the position of the occupant's CG center of gravity forward / backward within This footprint allows the vehicle to be appropriately configured for stability and maneuverability across a wide range of occupant sizes.

Support assembly 50 can be mounted to base 12 in a plurality of different angular positions. These positions allow the tilt range to be modified to suit the needs of a particular vehicle occupant. The modification of the first position allows the seat assembly 14 to tilt in a range of approximately 5 ° anterior to approximately 50 ° posterior. The modification of the second position allows the seat assembly 14 to tilt in a range of about 0 ° to about 55 ° rearward. Modifying the third position allows the seat assembly 14 to tilt in a range of approximately 5 ° posterior to approximately 60 ° posterior. A greater range of posterior tilt provides greater pressure relief to the ischial tuberosities. A greater anterior tilt range helps transfer the vehicle occupant in and out of the vehicle 10 and allows an occupant to

ES 2 389 730 T3 propel with your feet. These Tilt ranges allow the Tilt range to be tailored to the needs of a particular occupant.

Rocker 144 according to an alternative embodiment of the invention may be in the form of a round steel tube, as shown partially, in cross section, in Fig. 11. Rocker 144 is formed in a curve preferably having a constant radius or a substantially constant radius. This rocker 144 performs the same function as rocker 46 according to the preferred embodiment of the invention. Rocker 144 is attached to seat frame 20. Rocker 144 may be secured to support assembly 50, for example, by means of a plurality of rollers, one or more rollers 186 above rocker 144 and one or more rollers 187 below. The angle of inclination may be set by the alternate lock assembly 142, which may be located within the support assembly 198. Lock plates 146 have holes 192 through which rocker 144 passes. These holes 192 are slightly oversized relative to the diameter of the rocker 144. The plates 146 pivot about their upper ends. Spring 148 located between plates 146 forces plates 146 to pivot away from each other and lean against rocker 144 to lock rocker 144 in place relative to side tube 40 of base 12. This ensures the angle of inclination. of the seat frame 20. The plates 146 are opposed to each other so that when the seat frame 20 is tilted in one direction, the back plate in the direction of travel of the rocker 144 bears against the rocker 144 and prevents the seat frame 20 from slipping. tilt. Cable 150 is preferably a lever actuated cable that is secured through plates 146 such that when the lever (not shown) is tightened, the plates 146 pivot toward each other. As plates 146 pivot toward each other, the axes of holes 192 within plates 146 align with the arc of rocker 144 and release rocker 144 to allow rocker 144 to slide freely as seat frame 20 tilts. .

The invention described herein can easily be adapted to a battery-powered actuator or motor that could drive the tilt angle of the seating system. This adaptation could allow the vehicle's tilt function to be actuated by a control device that is accessible by the attendant or occupant of the vehicle. In the same way, the center of gravity of the seating system described herein could be mounted on a base with a power source, so that the wheels of the vehicle can be driven by a motor.

The present invention is not intended to be limited to the embodiments shown and described above. The base and seat assembly illustrated and described above is provided for illustrative purposes only. Other seat frames and bases may be suitable for carrying out the invention. Rockers are also provided for illustrative purposes. It should be understood that one or more rails, other than the rocker arms shown and described, having radius curves with a center of curvature that is coincident or substantially coincident with the center of gravity of the vehicle occupant, may be suitable for carrying out the invention. The rails may be supported by one of more suitable rollers, ramps, or other low friction members that allow the seat frame to rotate relative to the base. Seat frame adjustments, including adjustments to the seat, seat back and footrest assemblies, can be made in ways other than those listed above. It should further be understood that the vehicle may or may not adapt to growth, and further that the adaptation to growth may be performed in a manner other than that described. It should also be appreciated that the seat frame and support assembly may be adjustable in a manner other than that described.

The present invention can achieve a truly stationary center of gravity during tilting. Minimal effort on the part of the attendant or vehicle occupant may be required when the seat assembly is tilted. A raising or lowering of the occupant's center of gravity may not be required to tilt the seat assembly. Because the tilt is preferably limited to pure rotation, the only effort required can then be regulated to overcome friction in the system.

The vehicle occupant should not experience a sensation of loss of balance while leaning. The sensation experienced during the tilt of the center of gravity should be more reassuring for the occupant and less likely to induce inadvertent reactions that could potentially injure the vehicle occupant.

The present invention may also be advantageous in that the vehicle occupant's center of gravity can remain substantially stationary with respect to the base, thereby increasing the stability of the vehicle and allowing for a shorter base length. A shorter base frame increases vehicle maneuverability and creates a smaller overall footprint for the vehicle, allowing it to fit within tighter limits.

Finally, the present invention allows the weight distribution on the front and rear wheels of the vehicle to remain constant while the seat frame 20 is tilted. Well-defined weight distribution helps control and maneuver the vehicle.

ES 2 389 730 T3

The principle and mode of operation of the present invention have been explained and illustrated in its preferred embodiment. However, it should be understood that the present invention may be practiced in a manner other than that specifically explained and illustrated without departing from the scope of the claims.