Patent Description:
To aid people with physical limitations, there are several styles of rollable chairs and wheelchairs, including those that can be transformed to rollators (walkers).

<CIT> discloses a walker with a seat assembly that assists a user in rising from a seated position or sitting from a standing position. The seat assembly is mounted in a frame and includes a gas spring that deflects the seat assembly while the user is rising from the seat or dampens the deflection of the seat when the user is sitting.

<CIT> discloses a seating and walking wheelchair with an active seat and a frame. The active seat is configured to move from a seated position to a standing position. The active seat includes a seat back with an upper end and a lower end, and a seat bottom with a front end and a rear end. The rear end of the seat bottom is rotatable about a movable pivot.

<CIT> discloses a chair is operated by a pair of screw shaft-type linear actuators extend from a frame, and which may have a split seat with a drop-away front portion. One or more motors operate the screw shafts to raise the rear seat portion without changing its angular orientation. Connector links interconnect the frame with the front seat portion to drop it downwardly from under the user's thighs, while the back seat portion rises to assist the user to stand.

US patent <CIT> discloses a seating and walking wheelchair device, which also functions as a stander and a hands-free walker. The device raises the user to a standing position from a seated position, allowing the user to propel the device by the user's legs and feet. As the seat is raised, the seat swings from generally horizontal first position to a generally vertical second position, and vice versa.

<CIT> discloses a mobility-assistance apparatus including a wheelchair with a seat and frame and a walker coupled and integrated into the wheelchair. The walker has a seat lift mechanism.

<CIT> discloses a wheelchair with a frame, a seat and apparatus for moving the seat between lowered and raised positions. A translating mechanism is attached to the frame and the seat and provides translational movement of the seat that is forwards and upwards. An assist means generates a force to move the seat from the lowered to the raised position. The seat supports the user in a seated position; and in the raised position the occupant is in a mounted stance with a major part of the occupant's weight supported.

<CIT> discloses apparatus for moving a seat of a wheelchair between lowered and raised positions via a translating mechanism that moves the seat forwards and upwards.

<CIT> describes a reconfigurable wheeled personal mobility device.

<CIT> describes a seat structure with sit-to-stand feature.

<CIT> describes an elevating walker chair and convertible seat.

According to the invention there is provided a foldable user-support device configurable to be positioned on a ground surface comprising:.

In accordance with a first embodiment useful for understanding the invention, there is provided a user-support device configured to be rollable on a ground surface, comprising:.

The above features can allow the device to be used as a bi-directional rollable user-support device operable in at least two of the following three modes:.

Thus, in accordance with a second embodiment useful for understanding the invention, there is provided rollable user-support device configured to be rollable on a ground surface, the device comprising:.

In accordance with a third embodiment useful for understanding the invention, there is provided a user-support device configured to be rollable on a ground surface, the device comprising:.

In accordance with a fourth embodiment useful for understanding the invention, there is provided a user-support device configured to be rollable on a ground surface, the device comprising:.

In the device of the this embodiment, the safety arrangement can comprise a seat manipulation mechanism operable to move the seat, with a user seated thereon, between a lower rearward seating position and an elevated forward seating position in which the seat has a seating length shorter at a front area thereof relative to that in the lower rearward seating position to facilitate the user's standing up from his seated position. Alternatively or in addition, the safety arrangement can comprise one or both of the following: at least one roll prevention mechanism operable to prevent the front wheels from rolling on the ground surface when the seat is in its elevated forward seating position and at least one swivel prevention mechanism operable to prevent swiveling of the front wheels, when their rolling is prevented.

The device of each of above embodiments can be a bi-directional rollable user-support device and have both front and rear wheels rollable and swivelable.

The seat of the device of each of above embodiments can be capable of being brought from the elevated forward seating position into a folded position in which at least a portion of the seat has an orientation different from that in the elevated forward and lower rearward seating positions.

The device of each of the above embodiments can thus have a seat folding mechanism attaching the seat to the frame and operable to move the seat between the folded position and the unfolded position being the elevated forward seating position.

The device of each of the above embodiments can comprise a second swivel prevention mechanism activatable at least indirectly by the seat folding mechanism and operable to prevent the first wheels from swiveling when the seat folding device is in the folded position.

The device of each of the above embodiments can thus be operable in the following three modes:.

In accordance with a fifth embodiment useful for understanding the invention, there is provided a bi-directional user-support device operable in, and manipulable between a first, chair mode, in which the device is rollable in a first direction with a user sitting thereon, and a second, rollator mode, in which the device is rollable in a second direction opposite to the first direction, by a standing user facing in the second direction, the device comprising:.

In the device of each of the above embodiments, the seat can have a seating length which is shorter at a front area thereof when the seat is in the elevated forward position relative to that in the lower rearward seating position.

More particularly, the seat can have a main, rearward seat portion and an auxiliary forward seat portion and is manipulable between the following three positions:.

In the device of each of the above embodiments, the seat manipulation mechanism and the seat folding mechanism can be considered as a single seat manipulation and folding mechanism operable to move the seat between the lower seating state and the elevated seating state and between the elevated seating state and the folded state.

In accordance with a sixth embodiment useful for understanding the invention, there is provided a foldable user-support device configurable to be positioned on a ground surface and comprising:.

The device of each of the above embodiments, can further have each of the features described below.

The main seat portion and the auxiliary seat portion can have a juxtaposed disposition when the seat is in its lower rearward position, allowing the two portions together to accommodate a seated user in the lower rearward seating position of the seat, and wherein the auxiliary portion is operable at least indirectly by the seat manipulation mechanism to change its orientation so as to reduce the seating length of the seat, when the seat is moved into its elevated forward seating position, allowing only the main portion to accommodate a seated user in the elevated forward seating position.

The main seat portion can have the same orientation in the elevated and lower positions allowing it to support a user in both these positions.

The auxiliary seat portion can be positioned lower than the main seat portion and oriented transversely thereto when the seat is in the elevated forward position.

The seat manipulation mechanism can include at least one piston configured to store energy when the seat is moved towards the lower rearward position, and to release its stored energy when the seat is moved towards its elevated forward position.

The at least one roll prevention mechanism can comprise a roll prevention member associated with each first wheel and manipulable between a roll-enabling state in which the front wheel can be rolled and a roll-arresting state in which the front wheel is prevented from rolling; and a roll-prevention trigger member activatable at least indirectly by the seat manipulation mechanism when the seat is brought thereby into elevated forward seating position, and operable to bring the roll prevention member into the roll-arresting state.

The at least one swivel prevention mechanism can be operable to change the state of the first wheels from a swivel-enabling state, when the seat is in the lower rearward seating position, into a swivel arrested state in which the first wheels are prevented from swiveling when the seat is in the elevated forward seating position.

The at least one first swivel prevention mechanism can comprise a swivel arresting member associated with the first wheel and manipulable between a swivel-enabling state in which the swivel-enabling state of the first wheel is allowed, and a swivel-arresting state in which the swivel arresting member prevents the first wheel from swiveling; and a swivel-prevention trigger member activatable at least indirectly when the roll-prevention trigger member brings the roll prevention member into the roll-arresting state and operable to bring the swivel arresting member into the swivel-arresting state.

The frame can be rigid and at least its legs and, optionally, the entire frame can be non-foldable.

The seat manipulation mechanism can be connected to the first legs of the frame.

The roll prevention mechanism and the swivel prevention mechanisms can comprise activating elements extending within the front legs, via which these mechanisms are connected to the seat manipulation mechanism.

The frame can comprise a lower portion and an upper portion extending upwardly therefrom, and wherein the lower portion comprises the first and second legs and a strengthening bar connecting between the second legs.

The frame can comprise a right and a left frame member, each having a frame member lower portion with one first and one second leg, and a frame member upper portion.

The device can further a pair of extendable user-support arms connected to the frame member upper portions and operable to transition between a lower arm position in which a part of the arms is located in the frame upper portions for use when the device is in the first mode, and an extended arm position for use at least when the device is in the second mode.

All mechanisms of the device can be free of electrical connections and electrical power source.

In the folded state of the seat, at least most of the seat can extend along the frame, in a side view of the device.

The at least one roll prevention mechanism and the at least one first swivel prevention mechanism can be actuatable simultaneously.

The device can comprise a backrest which maintains its orientation when the seat is in the lowered rearward seating position and in the elevated forward seating position, in which the seat is disposed farther from the backrest than in the lower rearward position.

The backrest can be operably connected to the frame so as to be moveable between: a backrest deployed position in which the backrest is spaced rearwardly from the seat, at least a majority thereof is disposed above the plane defined by the seat, and the seat is oriented transversely to this plane when the seat is in the lower rearward position, and a backrest folded state in which the backrest is disposed adjacent the seat and extends along the seat when the seat is in the folded position.

The device can further comprise a backrest folding mechanism operable to move the backrest between the deployed state and the folded state. The backrest folding mechanism can be operably connected with the seat folding mechanism so as to activate the seat folding mechanism when the backrest folding mechanism is actuated.

When the frame comprises the frame members having the upper and lower portions as mentioned above, the backrest can be connected at least to the frame member upper portions.

The backrest and the backrest folding mechanism can be such that in the deployed position the backrest forms with the plane defined by the seat when in the lower rearward seating position, a first angle and in the folded state, the backrest forms with said plane a second, acute angle smaller than the first angle. In the folded position of the backrest, at most of it can extend along the frame in a side view of the device.

In accordance with a seventh embodiment useful for understanding the invention, there is provided a bi-directional user-support device operable in, and manipulable between, a first, chair mode, in which the device is configured to accommodate a seated user facing in a first direction, and a second, rollator mode, in which the device is rollable at least in a second direction opposite to the first direction, by a standing user facing in the second direction, the device comprising:.

When the backrest of the device of this sixth embodiment is in the deployed position it can form with the plane defined by the seat when in the lower rearward seating position a first angle, and in the folded state, the backrest forms with said plane a second, acute angle smaller than the first angle. When the backrest is in the folded position, at least most of it can extend along the frame.

In the device of this sixth embodiment, the first wheels of the first and second legs can be rollable and swivelable.

The device of this embodiment can further comprise a seat manipulation mechanism operable to move the seat, with a user seated thereon, between an elevated forward seating position and a lower rearward seating position, the elevated forward seating position constituting the deployed position of the seat into which it can be unfolded.

The device of this embodiment can further comprise at least one roll prevention mechanism operable to prevent the first wheels from rolling on the ground surface when the seat is in its elevated forward seating position. Alternatively or in addition, the device can comprise at least one first swivel prevention mechanism operable to prevent swiveling of the first wheels when the seat is in the elevated forward seating position. In both cases the.

In the device of this embodiment, the orientation of the seat in the folded position is different from that in the elevated forward and lower rearward seating positions.

In the device of this embodiment, the seat folding mechanism can be operable to activate a second swivel prevention mechanism to prevent the first wheels from swiveling when the seat folding device is in the folded position.

The device of this embodiment can thus be operable in the following three modes:.

In the device of this embodiment, the seat can have a seating length which is shorter at a front area thereof when the seat is in the elevated forward position relative to that in the lower rearward seating position. More particularly, the seat can have a main, rearward seat portion and an auxiliary forward seat portion and is manipulable between the following three positions:.

In the device of this embodiment, the seat manipulation mechanism and the seat folding mechanism can be considered as a single seat manipulation and folding mechanism operable to move the seat between the lower seating state and the elevated seating state and between the elevated seating state and the folded state.

As mentioned above, in each of the above embodiments, the mechanisms can be connected to each other solely or at least mostly by mechanical connections so that each mechanism is mechanically activated by, or mechanically activates, or both, at least indirectly, at least one of the other mechanisms of the device, thereby allowing the device to be user-friendly, i.e. free of means requiring a user to coordinate/control the operation of the mechanisms in different modes of operation of the device. In particular, the backrest folding mechanism can be operable to mechanically activate the seat folding mechanism, in order to bring the seat from its elevated forward state into its folded state or vice versa, for the device to be used in the rollator mode. The one of these two mechanisms which is activated first to bring the device into the folded state can be activated manually, e.g. by a user pulling the backrest or pushing the seat, or by using a control button. The backrest folding mechanism or the seat folding mechanism can be operable to mechanically activate the corresponding swivel prevention mechanism to prevent swiveling of the first/front legs when the device is in the folded state, to facilitate its use as a rollator. The seat manipulation mechanism activated by a user's raising himself with the help of arms of the device or by pressing a control button, can be operable to mechanically activate the roll prevention mechanism and the corresponding swivel prevention mechanism to arrest/lock the first/front wheels when the seat is in the elevated forward seating position, thereby enabling the user to be safely supported by the device when sitting high or standing up.

As also mentioned above, in each of the above embodiments, at least a part of mechanical elements connecting between different mechanisms, such as elements involved in roll and swivel prevention ,can be disposed within the frame.

In each of the above embodiments, each of the first wheels of the device, i.e. the wheels operable as front wheels when the device in its neutral or first, chair mode, can be associated with a caster assembly comprising a swivel caster holding wheel and operable to allow swiveling of the wheel; the assembly comprising at least one roll prevention mechanism configured to prevent rolling of the wheel and at least one swivel prevention mechanism different from the roll prevention mechanism operable to prevent swiveling of the wheel.

In the above caster assembly, the at least one swivel prevention mechanism can be a first swivel preventing mechanism and the assembly can further comprise at least one second swivel prevention mechanism actuatable separately and independently from the first swivel preventing mechanism.

Each of the first and second swivel prevention mechanism can be operable to lock the caster after its partial rotation to a first and a second predetermined angle, respectively, in the direction of rolling, the first and second angles being different.

Thus, in accordance with a still further embodiment useful for understanding the invention, there is provided a caster assembly for holding a wheel assembly comprising a swivel caster configured for connecting a wheel thereto and operable to allow swiveling of the wheel; the assembly comprising at least one roll prevention mechanism configured to prevent rolling of the wheel and at least one swivel prevention mechanism different from the roll prevention mechanism operable to prevent swiveling of the wheel.

The at least one swivel prevention mechanism can be a first swivel preventing mechanism and the assembly further comprises at least one second swivel prevention mechanism actuatable separately and independently from the first swivel preventing mechanism.

The at least one roll prevention mechanism and the at least one first swivel prevention mechanism are actuatable simultaneously.

The following detailed description of embodiments of the invention refers to the accompanying drawings referred to above. Dimensions of components and features shown in the figures are chosen for convenience or clarity of presentation and are not necessarily shown to scale. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same and like parts.

Illustrative embodiments of the invention are described below. In the interest of clarity, not all features/components of an actual implementation are necessarily described.

<FIG> show a rollable user-support device that may be designed to support a user in either a ("lower") chair seating position (<FIG>) or in an elevated sitting position (<FIG>). The lower seating position is useful for several implementations, including use as a rollable and swivelable chair, including a desk chair and a conveniently maneuverable chair for use in compact places such as bathrooms and the like, which may be useful for positioning a handicapped or person with motor issues to closely approach a toilet or a car seat. The elevated sitting position is useful for providing support to a user who wishes to be in a relatively elevated position, such as when conversing with people who are standing, or facing and adjacent a kitchen or bathroom sink, and so on. The elevated position may also be useful for aiding a user to get to a standing position.

Alternatively or additionally, the rollable user-support device may be designed to allow specific control of the wheels, front wheels and/or rear wheels. In particular, the user support device may be configured to allow a combination of rolling and/or swiveling options, in particular via one or more mechanisms that control the wheels, which, in some designs is in conjunction with the particular seat position.

The rollable user-support device includes a rigid frame <NUM> including right and left frame members fixedly connected to each other (for example via a frame strengthening bar) having an upper portion and a lower portion, which is constituted by a front leg <NUM> and a rear leg <NUM>. Each of the front legs has a distal end <NUM> with at least one front wheel <NUM> disposed at those distal ends. Each of the rear legs <NUM> has a distal end <NUM> with at least one rear wheel <NUM> disposed at those distal ends. The wheels are illustrated as single wheels, however, they may be constituted by a set of wheels, such as a pair of wheels. At least front wheels <NUM> can be configured to be both rollable and swivelable, as will be described in further detail hereinbelow, with reference to <FIG>). For example, front legs <NUM> and rear legs <NUM> can include swivel casters <NUM> to provide for the rolling and swiveling feature, as is known; however, at least one particular design of the casters will be described in detail hereinbelow, with reference to <FIG>.

Frame <NUM> has a seat <NUM> operably connected thereto. Seat <NUM> may be a <NUM>-part seat, or a multi-part seat such as the illustrated <NUM>-part seat. Seat <NUM> is configured to be positionable in a lower rearward seating position (<FIG>) and in an elevated forward seating position (<FIG>). In such designs, the device includes a seat manipulation mechanism <NUM> configured to maneuver the seat between the lower rearward seating position and the elevated forward seating position. This seat manipulation mechanism <NUM> can be operated electrically; however, in particular designs, it can be operated entirely by mechanical means. The initial position of the device, in particular seat <NUM>, is the seat elevated position, ready for the device to be sat upon to bring to a lower seat state (chair mode) and ready to be folded to a folded state (rollator mode). The initial position can be brought into the lower seat position via seat manipulation mechanism <NUM> and can be actuated with the user's weight/force once the user sits thereon.

In the case of the <NUM>-part seat <NUM>, the seat includes a rearward seating portion <NUM> (which may interchangeably be referred to as a main seating portion <NUM> herein the specification and claims), which is intended for supporting the user's buttocks; and a forward seating portion <NUM> (which may interchangeably be referred to as an auxiliary seating portion <NUM> herein the specification and claims), which in the lower sitting position is intended to provide support to the user's thighs. In this <NUM>-part configuration, in the elevated position (<FIG>), forward seating portion <NUM> is designed to fold downward. As seen, rearward seating portion <NUM> maintains its orientation with respect to the ground while being moved from its lower position to its elevated position (and vice versa) - typically substantially horizontal. In particular designs, seat manipulating mechanism <NUM> is configured to fold a <NUM>-part seat, as will be described hereinbelow, with reference to <FIG>.

The device may also include at least one swivel prevention mechanism <NUM> configured to allow the front wheels <NUM> to be prevented from swiveling (in some designs independently, and in some designs in conjunction with the position of seat <NUM>, in particular, when the seat is in its elevated position, as will be described hereinbelow). Swivel prevention mechanism <NUM> may be constituted by known means, or using a particular design, as will be described hereinbelow, with reference to <FIG>).

The device may also include at least one roll prevention mechanism <NUM> configured to prevent front wheels <NUM> from rolling when the seat is in the elevated position. Such a configuration maybe advantageous for providing a stable base for a user in an elevated position, such as when adjacent a kitchen/bathroom sink, or the like. Roll prevention mechanism <NUM> may be constituted by known means, or by way of a particular design that is entirely mechanical, as will be described hereinbelow, with reference to <FIG>).

In some designs, the rollable user-support device is configured to include seat manipulation mechanism <NUM> and swivel prevention mechanism <NUM>. In some designs, the rollable user-support device is configured to include seat manipulation mechanism <NUM> and roll prevention mechanism <NUM>. In some designs, the rollable user-support device is configured to include swivel prevention mechanism <NUM> and roll prevention mechanism <NUM>. In some designs, the rollable user-support device is configured to include seat manipulation mechanism <NUM>; swivel prevention mechanism <NUM>; and roll prevention mechanism <NUM>.

Any one or all three of the aforementioned mechanisms may be operated by electrical means. However, in particular designs, at least one of the three aforementioned mechanisms is entirely constituted by mechanical means; in some particular designs, at least two of the three aforementioned mechanisms are entirely constituted by mechanical means; and in some particular designs, all three aforementioned mechanisms are entirely constituted by mechanical means.

In a particular example, seat manipulation mechanism <NUM> is operatable by the user, whilst roll prevention mechanism <NUM> and swivel prevention mechanism <NUM> are operable directly or indirectly by the seat manipulation mechanism <NUM> so that the change of the position of the seat triggers the change of the state of front wheels <NUM>. Thus, when the device is in its initial state ("high chair", neutral/ready for use mode), with its seat <NUM> in the elevated forward position, at least its front wheels <NUM> are prevented from rolling and swiveling until the seat is lowered into its lowered position (as a normal rollable chair) in which the front wheels are rollable and swivelable (released from their roll-prevention and swivel-prevention state). When the user (e.g. by shifting weight forward and rising) causes the seat manipulation mechanism <NUM> to start elevating seat <NUM>, the seat manipulation mechanism at least indirectly causes the roll prevention mechanism <NUM> and swivel prevention mechanism <NUM> to prevent the device from rolling and swiveling. The seat manipulation mechanism <NUM> can be controllable by a user manipulating with his center of gravity and/or a control system.

Best seen in <FIG> and <FIG>, seat manipulation mechanism <NUM> includes a pair of seat portion attachment brackets <NUM> connecting between rearward seating portion <NUM> and forward seating portion <NUM>. Seat portion attachment brackets <NUM> are pivotally attached at a relatively forward location of rearward seating portion <NUM>. Seat manipulation mechanism <NUM> also includes a swivel-prevention trigger member (<NUM>) in the form of a pair of forward seating portion-to-frame connection brackets <NUM> pivotally attached at upper ends thereof to the front or sides of forward seating portion <NUM>, for example respectively attached at a pivot points at seat portion attachment brackets <NUM>. At their lower ends, brackets <NUM> are pivotally attached to frame <NUM>.

Seat manipulation mechanism <NUM> also includes a pair of frame-to-rear seating linkages <NUM> pivotably connecting frame <NUM> to rearward seating portion <NUM>, at a location behind to where seat portion attachment brackets <NUM> are attached. Linkages <NUM> may include a set of pivotably connected linkage sections (three illustrated), including a lower linkage section <NUM>; an intermediate linkage <NUM>; and an upper linkage <NUM>, where the intermediate linkage is pivotable connected at its respective ends to the lower linkage and the upper linkage.

Suitable lengths of seat portion attachment brackets <NUM> in combination with suitable lengths of forward seating portion-to-frame connection brackets <NUM> and frame-to-rear seating linkages <NUM> can be chosen to ensure that rearward seating portion <NUM> remains in a generally horizontal orientation during manipulation of seat <NUM>, which, as noted above, is moved from a rearward lower position to an elevated forward position (and vice versa).

Seat manipulation mechanism <NUM> may be powered by manual means, for example by a crank or the like; or mechanical means using, for example, a spring.

However, in some particular designs, seat manipulation mechanism <NUM> includes a pneumatic seat movement assist mechanism that includes at least one piston <NUM> (<FIG>), and typically a pair thereof. Pistons <NUM> can store energy in a contracted state that is usable to elevate seat <NUM> and thus help the user to rise from the seat or to achieve their elevated seating position. Conversely, the relatively extended piston <NUM> is also useful so as to help the user sit in a lower position, as the piston can be configured to be slowly compressed thereby relieving the user from supporting their weight with their legs and/or arms while going to the lower (regular) sitting position.

Pistons <NUM> are pivotally attached at a lower end thereof to frame <NUM> and pivotally attached at an upper end thereof to the side or bottom of rearward seating portion <NUM>, typically at a relatively rear portion of the rearward seating portion.

The device shown in above-referenced <FIG> can be convertible from a chair into a rollator/walker by having the chair's front wheels function as rear wheels in the rollator mode. This functionally can be operably connected with the foldability of the seat. In particular, the device can include a seat folding mechanism operable to bring the seat, and specifically its rearward seating portion, from an elevated state, when the front wheels are arrested, into a folded state in which the seat or at least its rearward seating portion is folded in a position substantially parallel to an upper portion of the frame. The seat folding mechanism can be so connected, at least indirectly, with a wheel manipulation mechanism as to prevent the wheels, now functioning as rear wheels, of the rollator from swiveling, when the seat is brought into the folded state. In particular, to cause the rollator's rear wheels to be in alignment with the frame when the rollator is rolled.

<FIG> show a bi-directional rollable user-support device, which is adjustable between an elevated seating state (see also <FIG>) configured for the user facing in a first direction <NUM>; and a rollator/walker mode configured for the user to walk upright and be supported, while facing in a second direction <NUM>, opposite the first direction. In other words, the bi-directional user-support device is operable in and manipulable between a first mode (chair) allowing the user to sit on its seat either in elevated position, <FIG> with the wheels being arrested; or in a lower sitting position, <FIG>, in which the bi-directional rollable user-support device is rollable on a ground surface in first direction <NUM> with a user is sitting thereon, and a second mode (rollator/walker), in which the bi-directional rollable user-support device can be rolled by a standing user on the ground surface in second direction <NUM>.

The bi-directional rollable user-support device is configured to be operable in and manipulable between a first mode (chair), in which the device can be rolled on a ground surface in first direction <NUM> with a user sitting thereon, and a second mode (rollator/walker), in which the device is rollable by a standing user on the ground surface in second direction <NUM>, which is opposite to the first direction.

The bi-directional rollable user-support device includes the components noted with reference to <FIG>, namely: frame <NUM>; front legs <NUM>; rear legs <NUM>; swivel casters <NUM>, with rollable and swivelable front wheels <NUM> and rollable rear wheels <NUM> which in this case are also swivelable; and seat <NUM>.

As the device is bi-directional, the "front wheels" will be termed "first wheels" 28a; and the "rear wheels" will be termed "second wheels" 32a.

When the bi-directional rollable user-support device is in its first mode (chair or elevated chair; <FIG>), "first wheels" 28a are functioning as "front wheels", and are configured to roll and swivel, and the user is seated and faces in first direction <NUM>.

When the bi-directional rollable user-support device is in its second mode (rollator/walker; <FIG>), it is "second wheels" 32a that now are functioning as a "front wheels", and are configured to roll and swivel, and the user is standing and faces in second direction <NUM>.

Although frame <NUM> can be designed to provide support for the user while standing (e.g. rollator for a relatively short user; <FIG>, or wherein the frame is relatively tall), for convenience in the rollator/walker configuration, the bi-directional rollable user-support device typically includes a pair of upwardly extendable user-support arms <NUM> with handles <NUM>. In a particular design, frame <NUM> includes a pair of elongated arm receiving recesses <NUM> (<FIG>) configured to receive arms <NUM> and a mechanism to allow extension of the arms and to lock the arms in chosen arm extension positions. Such arm locking mechanisms are well known and will not be described.

The bi-directional rollable user-support device includes a seat manipulation and folding mechanism <NUM> operably attaching seat <NUM> to frame <NUM>. Mechanism <NUM> is configured to move seat <NUM> between a first (deployed) state (<FIG>), in the first mode of the device when the seat is in its elevated position, and a second (folded) state (<FIG>), in the second mode of the device (rollator/walker).

Seat manipulation and folding mechanism <NUM> may be constituted by known means, including electrically, or via a particular entirely mechanical design. In such a mechanical design (and wherein there is no backrest) may be constituted by the same components of seat manipulation mechanism <NUM>. To accomplish the folding, the user may press forward seating portion <NUM> backward in the direction of arrow <NUM> (<FIG>), whereby rearward seating portion <NUM> will fold like a book with the forward seating portion (<FIG>) both moving to a non-horizontal orientation.

The bi-directional rollable user-support device also includes a wheel manipulation mechanism <NUM> configured to enable at least first wheels 28a to swivel when the device is in its initial mode (<FIG>); and to enable second wheels 32a to swivel, while preventing the first wheels from swiveling when the device is in its rollator/walker mode (<FIG>). Wheel manipulation mechanism <NUM> may be constituted by known means, including electrically, or via a particular entirely mechanical design, as will be described hereinbelow, with reference to Figs. <NUM>-<NUM>. The device shown in <FIG> has a backrest <NUM> and armrests <NUM>, which might or might not be a part of the device and might, or might not, be folded when the seat is folded.

<FIG> show a bi-directional rollable user-support device in which backrest <NUM> is foldable together with the seat folding. The bi-directional rollable user-support device is configured to be operated in, and manipulable between a first mode (chair), in which the device is configured to accommodate a seated user facing in a first direction, and a second mode (rollator), in which the device is rollable in the second direction, opposite to the first direction and configured to support a standing user; and in particular to control the position of seat <NUM> with backrest <NUM> with respect to frame <NUM>. This seat and backrest positioning may advantageous to the user, for example and without limitation to any actual implementation, to provide a better line of vision and/or for more compact folding, which may be useful for storage and/or transportation of the device.

The bi-directional rollable user-support device includes frame <NUM> with front legs <NUM> and rear legs <NUM> connected thereto. At least one first wheel 28a is attached to distal ends <NUM> of each of front legs <NUM>, in which the wheels are at least configured to roll and optionally to swivel. At least one second wheel 32a is attached to distal ends <NUM> of each of rear legs <NUM>, in which the second wheels are configured to roll and swivel. Seat <NUM> is operably connected to the frame <NUM>. The backrest <NUM> operably connected to frame <NUM>, either directly (i.e. the frame may be suitably configured) or by other means such as via armrests <NUM>.

The bi-directional rollable seat-folding user-support device also includes a seat and backrest folding mechanism <NUM> configured to fold and unfold the seat <NUM> and backrest <NUM> and operably attaching seat <NUM> and backrest <NUM> to frame <NUM>. Backrest <NUM> is configured to be connected at least indirectly to seat and backrest folding mechanism <NUM> which is operable to move backrest <NUM> between a first (deployed, user back-support) state in the first mode (chair) of the device, in which the backrest is positioned at least partially above frame <NUM> (<FIG>), and a second (folded) state in the second mode of the device (rollator), in which at least a portion of frame <NUM> is above the backrest (<FIG>).

<FIG> show seat and backrest folding mechanism <NUM> in a mid-way state between an elevated seating position of the bi-directional rollable seat-folding user-support device and a folded position thereof. It can be seen that as seat <NUM> is transitioning, backrest <NUM> is being lowered and also moving to a position substantially parallel to the seat, and to the upper portion of frame <NUM>, as illustrated in <FIG>.

Seat and backrest folding mechanism <NUM> can be operated by an electric means; however, in particular designs, mechanism <NUM> is entirely mechanical. In such a mechanical design, seat and backrest folding mechanism <NUM> may include seat manipulation mechanism <NUM> in combination with components configured to arrange the position of backrest <NUM>.

With reference also to <FIG>, seat and backrest folding mechanism <NUM> is depicted, including seat manipulation mechanism <NUM>, which makes up a portion of mechanism <NUM>.

<FIG> illustrates seat and backrest folding mechanism <NUM> in an initial state of the device, prior to folding, with seat <NUM> is its elevated position and backrest <NUM> is a user back-supporting position. Backrest <NUM> is pivotally connected to armrest <NUM>, which is pivotally attached to frame <NUM>. In <FIG>, seat <NUM> and backrest <NUM> are at an early stage of their folding transition. In <FIG>, seat <NUM> and backrest <NUM> are fully folded and in a substantially parallel juxtaposition (in some designs within an angle of <NUM> degrees) and also substantially parallel (in some designs within an angle of <NUM> degrees) to an upwardly extended portion <NUM> of the upper portion of frame <NUM>. <FIG> illustrate similar folding positions. In designs without backrest <NUM> or armrests <NUM>, the device's folded position is as illustrated in <FIG>.

Seat and backrest folding mechanism <NUM> includes a plurality of linkages, for example three linkages, including an upper linkage <NUM> that, at its upper end, is pivotally connected to frame <NUM>, while being fixedly connected to armrest <NUM>. An intermediate linkage <NUM> is pivotally connected at its upper end to the lower end of upper linkage <NUM>. Lower linkage <NUM> is pivotally connected at its upper end to the lower end of intermediate linkage <NUM>, and at its lower end to connection bracket <NUM> of seat manipulation mechanism <NUM>. Intermediate linkage <NUM> has an elongated slot <NUM> therein that receives a pivot pin <NUM>, which is fixed to upwardly extending portion <NUM> of frame <NUM>.

Connection bracket <NUM> has a folding mechanism pin <NUM> (<FIG>) configured to slide along the upper edge of lower linkage section <NUM> between a bend or curve in lower linkage section <NUM> and a pin-receiving recess <NUM> at the upper end of lower linkage section <NUM>. In the elevated seat position, pin <NUM> is located adjacent the bend/curve of lower linkage section <NUM>, and in the device's folded state (rollator), pin <NUM> is disposed in recess <NUM>.

To fold the device, namely to fold seat <NUM> and backrest <NUM> (as well as armrest <NUM>), the user pulls on the backrest in the general direction <NUM> (<FIG>). As a result, upper linkage <NUM> is moved in a clockwise direction <NUM> causing the upper end of intermediate linkage <NUM> to move in a direction similar to direction <NUM> and to thus pivot clockwise about pivot pin <NUM>. As a result, the lower end of intermediate linkage <NUM> moves in the opposite direction (leftward in the Figs. ) to thereby pull on lower linkage <NUM>. As lower linkage <NUM> is attached to connection bracket <NUM>, and that bracket is pivotally attached at its lower end to frame <NUM>, bracket <NUM> pivots toward backrest <NUM>. When in the fully folded state, pin <NUM> is received in recess <NUM>, thereby reversibly securing the folded state, and the device is ready to be used as a rollator.

<FIG> show a foldable user-support device including frame <NUM>; front legs <NUM>; rear legs <NUM> and seat <NUM>, operably connected to the frame. Seat <NUM> has rearward seating portion <NUM> and forward seating portion <NUM> and is configured to be maneuverable between three states: (a) a lower seating state (<FIG>), in which rearward seating portion <NUM> and forward seating portion <NUM> are substantially aligned; (b) an elevated seating state (<FIG>), in which rearward seating portion <NUM> and forward seating portion <NUM> are angled with respect to each other at a first angle <NUM>; and (c) a folded state (<FIG>) in which rearward seating portion <NUM> and the forward seating portion <NUM> are angled with respect to each other at a second angle <NUM>, which is smaller than the first angle <NUM>.

Foldable user-support device also includes a seat folding mechanism <NUM> configured to maneuver seat <NUM> between the lower seating state (<FIG>) and the elevated seating state (<FIG>) and also between the elevated seating state and the folded state (<FIG>).

<FIG> show a caster assembly including swivel caster <NUM> having a caster shaft <NUM> in which the caster assembly is configured to allow swiveling of the wheel. The caster assembly includes a roll and swivel control mechanism <NUM> configured to allow wheel <NUM> to roll and to prevent swiveling thereof. In particular designs, swivel control mechanism <NUM> is configured to prevent both rolling and swiveling of wheel <NUM>.

Roll and swivel control mechanism <NUM> may be constituted by an electrically controlled mechanism; however, in particular designs it is an entirely mechanical mechanism, as exemplified in <FIG><FIG>and <FIG>Roll and swivel control mechanism <NUM> includes roll prevention mechanism <NUM> and swivel prevention mechanism <NUM>. It is further noted that the entirely mechanical swivel control mechanism <NUM> can be constituted by a mechanism configured to apply immediate prevention of wheel swiveling, for example via a clamp or other such means.

Roll prevention mechanism <NUM> is integrated and/or associated with swivel caster <NUM> and caster shaft <NUM>. Caster shaft <NUM> has a longitudinal tunnel <NUM> running therethrough and configured to receive a roll brake rod <NUM>, which may look like a carpentry nail with nail-heads on both sides. At its lower end, roll brake rod <NUM> is attached to a proximal end of roll prevention member <NUM> in the form of a roll brake lever <NUM>. At its upper end, roll brake rod <NUM> is attached to a roll brake actuator <NUM>.

Roll brake lever <NUM> is exemplified by a see-saw type lever pivotally attached to swivel caster <NUM>, for example at about the mid-point of the lever, and at the free end of lever <NUM> there is a brake pad <NUM>. At its upper end, roll brake actuator <NUM> is attached to one end of a roll brake actuating cable <NUM> (the right end of cable <NUM> in the Figs). A lower portion of roll brake actuator <NUM> is pivotably attached to frame <NUM>.

Roll prevention mechanism <NUM> also includes a roll brake spring <NUM> held between roll brake actuator <NUM> and a swivel pin insertion lever <NUM> (described below) designed to actuate a mechanism for limiting wheel swivel, described hereinbelow. Cable <NUM> may longitudinally pass though (coil) spring <NUM>.

In <FIG> and <FIG>, roll brake spring <NUM> urges roll brake actuator <NUM> to pivot downward (clockwise in the Figs) thereby lowering roll brake rod <NUM>. As a result, roll brake lever <NUM> seesaws (counter-clockwise in the Figs) to produce a gap between brake pad <NUM> and wheel <NUM>. Thus, wheel <NUM> may roll.

Conversely, wheel <NUM> is prevented from rolling when cable <NUM> pulls on pivot roll brake actuator <NUM> to pivot the roll brake actuator (counterclockwise in the Figs) and raise the top of the roll brake actuator (spring <NUM> is compressed). This moves roll brake rod <NUM> upward whereby brake lever <NUM> seesaws (clockwise in the Figs) to force brake pad <NUM> downward to prevent wheel <NUM> from rolling.

Cable <NUM> is attached at its distal end (the left end in the Figs) to a roll-prevention trigger member <NUM> in the form of a roll prevention actuating member <NUM>, which is fixed at a predetermined angle with respect to linkage section <NUM> of seat manipulation mechanism <NUM>.

With reference to <FIG>, the relationship between the lower and elevated position of seat <NUM> and the rolling of wheel <NUM> is now described. When seat <NUM>, in particular rearward seating portion <NUM> thereof, is moved from its lower rearward position (<FIG>) to its elevated forward position (<FIG>), roll prevention mechanism <NUM> is actuated and wheel <NUM> is prevented from rolling.

Moving to the elevated seat position, i.e. when the user is getting up from a fully sitting to a semi-seated position, linkage <NUM> is moved from its position in <FIG> to its position in <FIG>. This movement pivots linkage section <NUM> clockwise and cable <NUM> is pulled, preventing rolling of wheel <NUM> (<FIG>). When moving from an elevated seat position to a lower sitting position, linkage section <NUM> moves counterclockwise, whereby rolling of wheel <NUM> is allowed (<FIG> and 19B).

With continued reference to <FIG>, swivel prevention mechanism <NUM> is now described. In particular designs, swivel prevention mechanism <NUM> may be configured to provide two levels of swivel prevention, a first level of swivel prevention provided by a first swivel prevention mechanism 300a, in which swivel caster <NUM> can only rotate a relatively limited amount, for example up to <NUM> degrees, and then is arrested; and a second level of swivel prevention provided by a second swivel prevention mechanism 300b in which the caster can swivel until it is aligned with a direction of rolling, and then further swiveling is prevented. The limited swiveling may be useful for safety purposes as it limits the movement of the front of the device when seat <NUM> is elevated so that the device stably supports the user.

First swivel prevention mechanism 300a will be described first, in which caster shaft <NUM> has a plurality (e.g. twelve) swivel limiting recesses <NUM> equally spaced about the shaft. For such purpose, caster shaft <NUM> may include a larger diameter portion <NUM> where swivel limiting recesses <NUM> are disposed in a substantially horizontal plane. Swivel limiting recesses <NUM> are dimensioned to receive a swivel arresting member <NUM> in the form of a swivel limiting pin <NUM> whose distal end fits into the recesses. Swivel limiting pin <NUM> is slidingly held horizontally at the same plane of recesses <NUM> by a pin holder <NUM>.

At its proximal end, swivel limiting pin <NUM> interfaces with a lower end of a swivel pin insertion lever <NUM> so that the insertion lever can urge the pin into any one of recesses <NUM> when aligned therewith. Swivel pin insertion lever <NUM> is pivotally attached to pin holder <NUM> in a seesaw manner. The upper end of swivel pin insertion lever <NUM> interfaces with roll brake spring <NUM>.

As noted above, when seat <NUM> is elevated, cable <NUM> is pulled. In addition to actuating roll prevention mechanism <NUM>, pulling on cable <NUM> also actuates the limited swivel assembly. Cable <NUM> pulls on roll brake actuator <NUM>, which compresses spring <NUM> so as to force the upper end of swivel pin insertion lever <NUM> outward (to the left in the Figs. Swivel pin insertion lever <NUM> thus pivots (counterclockwise in the Figs) to urge swivel limiting pin <NUM> into swivel limiting recesses <NUM>. If swivel caster <NUM> swivels up to <NUM> degrees, one of the swivel limiting recesses will align with swivel limiting pin <NUM> and the pin will enter the aligned recess. Thus, swiveling will be prevented beyond a limit, e.g. <NUM> degrees in the exemplary design wherein caster shaft <NUM> has twelve equally spaced recesses <NUM>. As such, the user will have a stable high chair in the elevated seat position.

In this context, the term "swivel prevention", its derivatives, uses within other terms and the like, herein the specification and claims, will be understood to mean swivel arresting after a predetermined swivel limit (spinning of wheels <NUM>). This predetermined swivel limit is a function of the number of recesses <NUM>.

Second swivel prevention mechanism 300b, via which swivel caster <NUM> can swivel until it is aligned with the direction of rolling, will now be described. Here, swivel prevention mechanism <NUM> includes a swivel prevention cable <NUM> attached to an upper end of a swivel alignment lever <NUM>. Swivel alignment lever <NUM> is pivotally attached to pin holder <NUM> in a seesaw manner, for example, at the same pivot point as lever <NUM>. A lower end of swivel alignment lever <NUM> interfaces with a swivel alignment and prevention pin <NUM>, which is generally horizontally oriented. Swivel alignment and prevention pin <NUM> is disposed in the same plane as a single pin receiving recess <NUM> disposed in larger diameter portion <NUM>. Single pin receiving recess <NUM> is located in portion <NUM> so as to align with swivel alignment and prevention pin <NUM> when wheel <NUM> trails behind shaft <NUM>. Thus, wheel <NUM> rolls parallel (in alignment) with the forward movement of the device in the rollator configuration, and prevent swiveling within <NUM> degrees of wheel swivel.

In this context, the term "swivel prevention", its derivatives, uses within other terms and the like, herein the specification and claims, will be understood to mean swivel arresting after a predetermined swivel limit (spinning of wheels <NUM>). This predetermined swivel limit is no greater than <NUM> degrees, in particular until casters <NUM> of first wheels 28a align with frame <NUM>.

Summarizing, <FIG> illustrate roll and swivel control mechanism <NUM> in a swivel and roll enabled state i.e. where neither swivel prevention mechanism <NUM> nor roll prevention mechanism <NUM> are actuated. <FIG> illustrate roll and swivel control mechanism <NUM> in a roll only state (swivel arrested/locked), i.e. with swivel prevention mechanism <NUM> operated. <FIG> illustrate roll and swivel control mechanism <NUM> in a locked/arrested state (roll and swivel arrested/locked), i.e. with swivel prevention mechanism <NUM> and roll prevention mechanism <NUM> both actuated.

A bi-directional rollable user-support device having all the mechanisms described above will now be described with reference to the aforementioned Figs.

In such a design, which can be considered an "all-inclusive" design of the bi-directional rollable device, there are:.

Movement between the three possible seat states operably effects the three possible first wheel states, namely, (a) moving seat <NUM> from its lower rearward position to its elevated forward position actuates mechanism <NUM> resulting in the first wheels changing state from a rollable and swivelable state to a swivel prevention state (and vice versa when the seat is moved from the elevated forward position to the rearward lower position); (b) moving backrest <NUM> from its user back-support position to its folded position (rollator) actuates mechanism <NUM> resulting in first wheels 28a changing state from a non-rollable and non-swivelable state to a rollable non-swivelable state and first wheels functioning as rear wheels. Conversely, moving backrest <NUM> from its folded position (rollator) to its non-folded back supporting state results in first wheels <NUM> returning to functioning as front wheels, and those wheels being in a non-roll swivel prevention state.

In particular, a rollable user-support device is provided that includes all the mechanisms described above, reference to the aforementioned Figs.

Specifically, the rollable user-support device is configured to be rollable on a ground surface and includes a rigid frame <NUM> (as described above) having a pair of first legs <NUM> and a pair of second legs <NUM> (as described above). Each first leg <NUM> has a first leg distal end <NUM> at which at least one first wheel 28a is attached and the wheels is rollable and swivelable (as described above). Each second leg <NUM> has a rear leg distal end <NUM> at which at least one second wheel 32a is attached and those wheels are rollable and swivelable (as described above).

The rollable user-support device includes seat <NUM> (as described above) operably connected to frame <NUM> and is positionable in three positions: a lower rearward seating position; an elevated forward seating position; and a folded position. A seat folding mechanism (as described above with reference to mechanism <NUM>) is operable to manipulate seat <NUM> between the folded position and an unfolded position (the elevated forward seating position). Seat manipulation mechanism <NUM> (as described above) is operable to move seat <NUM>, with a user seated thereon, between the lower rearward seating position and the elevated forward seating position.

At least one roll prevention mechanism <NUM> (as described above) is activatable, at least indirectly, by seat manipulation mechanism <NUM> and is operable to prevent first wheels 28a from rolling on the ground surface when seat <NUM> is brought into its elevated forward seating position. At least one first swivel prevention mechanism 300a (as described above) is activatable, at least indirectly, by seat manipulation mechanism <NUM> and is operable to prevent swiveling of first wheels 28a, at least after their rolling is prevented in the seat's elevated forward position. At least one second swivel prevention mechanism 300b (as described above) is actuatable by seat manipulation mechanism <NUM> of mechanism <NUM> and is operable to prevent the swiveling of first wheels 28a when seat <NUM> is brought into its folded position.

The rollable user-support device is a bi-directional rollable user-support device operable in the following three modes:.

In some designs, backrest <NUM> (as described above) is operably connected to frame <NUM> so as to be moveable between (a) a backrest deployed position in which the backrest is spaced rearwardly from seat <NUM> and at least a majority thereof is disposed above a plane defined by the seat and is oriented transversely to this plane when the seat is in its lowered rearward position, and (b) a backrest folded state in which the backrest is disposed adjacent the seat and extends along a plane of the seat when the seat is in the folded position. Backrest folding mechanism <NUM> is operable to move backrest <NUM> between the deployed state and the folded state.

In some designs, a backrest folding mechanism (as described above with reference to mechanism <NUM>) is operably connected with a seat folding mechanism (as described above with reference to mechanism <NUM>) so as to actuate the seat folding mechanism when the backrest folding mechanism is actuated. The backrest folding mechanism may be operably connected with the seat folding mechanism so as to actuate folding of backrest <NUM> and seat <NUM> upon actuation of the backrest folding mechanism.

Seat <NUM> may be disposed farther from backrest <NUM> in the elevated forward position than in the lowered rearward position. Seat <NUM> may have a seating length which is shorter at a front area thereof when the seat is in the elevated forward position relative to that in the lower rearward seating position. Seat <NUM> may have main seating portion <NUM> (as described above) and an auxiliary seating portion <NUM> (as described above) operable to change orientation thereof relative to the main seating portion <NUM> when seat <NUM> is moved between the lowered rearward position and the elevated forward position.

Main seating portion <NUM> and auxiliary seating portion <NUM> may have a juxtaposed disposition when seat <NUM> is in its lowered rearward position, allowing the two portions together to accommodate a seated user in the lower rearward seating position of seat <NUM>, in which the auxiliary seating portion (<NUM>) is operable at least indirectly by the seat manipulation mechanism <NUM> to change its orientation so as to reduce the seating length of seat <NUM>, when the seat (<NUM>) is moved into its elevated forward seating position, allowing only main seating portion <NUM> to accommodate a seated user in the elevated forward seating position.

Main seating portion <NUM> may have the same orientation in the elevated and lowered positions allowing it to support a user in both these positions. The auxiliary seating portion <NUM> may be positioned lower than main seating portion <NUM> and oriented transversely thereto when seat <NUM> is in the elevated forward position.

Seat manipulation mechanism <NUM> may include at least one piston <NUM> (as described above) configured to store energy when seat <NUM> is moved towards the lower rearward position, and to release its stored energy when seat <NUM> is moved towards its elevated forward position.

Roll prevention mechanism <NUM> may include a roll prevention member <NUM> (as described above) associated with each first wheel 28a and be manipulable between a roll-enabling state in which front wheel <NUM> can be rolled; and a roll-arresting state in which the front wheel is prevented from rolling. Roll-prevention trigger member <NUM> (as described above) is activatable, at least indirectly, by seat manipulation mechanism <NUM> when seat <NUM> is brought thereby into its elevated forward seating position, and operable to bring roll prevention member <NUM> into the roll-arresting state.

Swivel prevention mechanism <NUM> (as described above) is operable to change the state of first wheels 28a from a swivel-enabling state, when seat <NUM> is in the lower rearward seating position, into a swivel arrested state in which first wheels 28a are prevented from swiveling when seat <NUM> is in the elevated forward seating position.

Swivel prevention mechanism <NUM> may include a swivel arresting member <NUM> (as described above) associated with front wheels <NUM> and manipulable between a swivel-enabling state in which the swivel-enabling state of the front wheels is allowed, and a swivel-arresting state in which swivel arresting member <NUM> prevents the front wheels <NUM> from swiveling. Swivel-prevention trigger member <NUM> (as described above) is activatable when the roll-prevention trigger member <NUM> brings the roll prevention member <NUM> into the roll-arresting state and operable to bring the swivel arresting member <NUM> into the swivel-arresting state.

Each first wheel 28a may be in the form of caster <NUM> (as described above) attached to first legs <NUM> by caster shaft <NUM> (as described above), and second swivel prevention mechanism 300b is operable to prevent, in the roll-only state and caster <NUM> is prevented from rotating more than <NUM> degrees about the caster shaft <NUM>.

Roll prevention mechanism <NUM> and swivel prevention mechanism <NUM> may include activating elements extending within front legs <NUM>, via which these mechanisms are connected to seat manipulation mechanism <NUM>.

Frame <NUM> may be rigid and its legs <NUM>, <NUM> may be unfoldable. Seat manipulation mechanism <NUM> may be connected to first legs 28a of frame <NUM>. Frame <NUM> may include a lower portion and an upper portion extending upwardly therefrom. The lower portion may include first and second legs <NUM>, <NUM> and a frame strengthening bar connecting between the second legs <NUM>.

Frame <NUM> may include right and left frame members, each member having a frame member lower portion with one first and one second leg <NUM>, <NUM>, and a frame member upper portion. Backrest <NUM> may be connected to the frame member upper portions.

The device may include a pair of extendable user-support arms <NUM> connected to the frame member upper portions. The arms <NUM> are operable to transition between a lower arm position in which a portion of the arms is located in the frame upper portions for use when the device is in its first mode, and an extended arm position for use at least when the device is in its second mode.

Claim 1:
A foldable user-support device configurable to be positioned on a ground surface comprising:
(a) a seat (<NUM>) having a main, rearward seat portion (<NUM>) and an auxiliary forward seat portion (<NUM>) and manipulable between the following three positions:
i) a lower rearward seating position, in which the main seat portion (<NUM>) and the auxiliary seat portion (<NUM>) are disposed adjacent each other and aligned to provide a pre-determined seating length along a horizontal plane;
ii) an elevated seating position, in which the main seat portion (<NUM>) maintains its orientation when the seat (<NUM>) is moved from the lower rearward seating, and at least a majority of the auxiliary seat portion (<NUM>) is lower relative to the main seat portion (<NUM>), and is oriented transversely thereto whereby the seating length of the seat (<NUM>) is reduced; and
iii) a folded position, in which the main seat portion (<NUM>) and the auxiliary seat portion (<NUM>) change their orientation relative to that in the lower seating position, and a length of their total projection on the horizontal plane is smaller than the reduced seating length of the seat (<NUM>) in the elevated seating position; and
(b) a seat manipulation and folding mechanism (<NUM>, <NUM>) configured to move the seat (<NUM>) between the lower rearward seating position and the elevated seating position and between the elevated seating position and the folded position.