Patent Description:
Embodiments of the present invention relate generally to an improved wheelchair and, more particularly, an all-terrain electric wheelchair that is easy to assemble, disassemble, store, and transport.

All-terrain wheelchairs are used to help people with mobility issues traverse across all-types of terrain. Notably, beaches are particularly difficult to traverse due to, for example, soft sand, dunes, rocky terrain, etc. Beach wheelchairs are most often manually propelled, although there are some electrically powered beach wheelchairs. However, these electrically powered beach wheelchairs are often very large, heavy, expensive, and difficult to transport. These issues discourage or prevent many individuals from being able to regularly use electrically powered beach wheelchairs. These issues also tend to discourage individuals from purchasing their own electrically powered beach wheelchairs. <CIT> discloses a powered vehicle for personal mobility comprising first and second frame parts.

Various embodiments described herein enable users to disassemble the wheelchair assembly to smaller components that are easier to carry, store, and transport. Some of the heaviest components in the wheelchair assembly may be electrical components such as the battery and the components associated with the motor. These components often possess an increased weight, which may be problematic or less desirable for all-terrain wheelchair assemblies that may require greater power to operate over different types of terrain. Various embodiments account for this by providing motor components on a separate motor subassembly that can be selectively attached or disengaged from the remainder of the wheelchair assembly, and the battery may be provided separately and mountable to a seat subassembly that is separate from the motor subassembly. By providing the battery in a separate subassembly from the motor subassembly, the overall weight of the motor subassembly may be greatly reduced and the overall weight of the seat subassembly (including the battery) may still be relatively light. In some embodiments, the battery may be further separated from the seat subassembly to further reduce weight of each carriable part (e.g., each subassembly). Thus, in some embodiments, the motor subassembly and the seat subassembly may both be easily carriable by a single person when carried separately. Furthermore, by providing the battery away from the motor components, the weight distribution of the wheelchair assembly as a whole may be improved.

By allowing for the wheelchair assembly to be broken down into various subassemblies, the subassemblies may be permitted to fit into smaller storage areas. For example, by breaking down the wheelchair assembly, the various subassemblies may be more easily stored in a trunk of a car or sports utility vehicle (SUV) (e.g., less than <NUM> cubic feet, less than <NUM> cubic feet, less than <NUM> cubic feet, less than <NUM> cubic feet, and preferably less than <NUM> cubic feet). (<NUM> cubic foot=<NUM>,<NUM> cubic meters). This may enable a larger number of individuals to use their own wheelchair assembly. In some embodiments, the wheelchair assembly may be assembled, disassembled, and stored without the requirement of vans, trailers, specialist lifts, or ramps, increasing its ease of use.

The motor subassembly may also be selectively added or removed from the seat subassembly, and this may give the user an option to remove the motor subassembly so that the seat subassembly is used by manually moving the seat subassembly. The motor subassembly may be designed in a manner that is easily retrofittable to existing wheelchairs or seat subassemblies.

According to the invention, there is provided a wheelchair assembly for easy assembly and disassembly according to claim <NUM>. Preferred features are set out in the dependent claims.

Example embodiments of the present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals generally refer to like elements throughout. For example, reference numerals <NUM> and <NUM> are both intended to refer to wheelchair assemblies, and elements <NUM> and <NUM> are both intended to refer to driven wheels. Additionally, any connections or attachments may be direct or indirect connections or attachments unless specifically noted otherwise.

As used herein, an occupant is intended to refer to a person sitting in the wheelchair assembly, and an assistant is intended to refer to a person other than the occupant that is assisting in moving, assembling, disassembling, storing, transporting, etc. the wheelchair assembly. A user is intended to refer to either the occupant or an assistant.

<FIG> illustrates a perspective view of an example wheelchair assembly <NUM>. The wheelchair assembly <NUM> may include various frames. For example, the wheelchair assembly <NUM> has a seat frame <NUM>, a backrest frame <NUM>, and a footrest frame <NUM>. The backrest frame <NUM> may include rear handles <NUM> where an assistant may grasp the rear handles <NUM> to push the wheelchair assembly <NUM>. Furthermore, the backrest frame <NUM> may include occupant armrests <NUM>. These occupant armrests <NUM> may provide armrests for the occupant to rest their arms. The occupant armrests <NUM> may be pivotable in the wheelchair assembly <NUM>. This may be beneficial to permit occupants to more easily exit the wheelchair assembly <NUM>. Furthermore, the pivotable nature of occupant armrests <NUM> may make the backrest frame <NUM> more compact when stored. However, the occupant armrests <NUM> may not be pivotable in other embodiments. Upholstery <NUM> may be provided on the various frames and components of the wheelchair assembly <NUM> to increase the comfort level for users. The upholstery, in some embodiments, may be designed for use with sandy environments, such as beaches (e.g., the upholstery may be easily washable).

Wheelchair assemblies provided herein may include various wheels. For example, the wheelchair assembly <NUM> may include front wheels <NUM>, driven wheels <NUM>, and anti-tip wheels <NUM>. The driven wheels <NUM> may require driven wheels <NUM> that are large in order for the wheels to effectively move in difficult terrains. In the illustrated embodiment, the driven wheels <NUM> possess a diameter of forty-nine (<NUM>) centimeters and a width of twenty-three (<NUM>) centimeters, but driven wheels <NUM> of other sizes may be used. Rotation of the driven wheels <NUM> may be generated by a motors <NUM> (see <FIG>) and the electrical components in the wheelchair assembly <NUM>. Further, in the wheelchair assembly <NUM>, the front wheels <NUM> and the anti-tip wheels <NUM> are not electrically powered, and these wheels are permitted to adjust in angular orientation and rotational speed based on adjustments at the driven wheels <NUM>. For example, the front wheels <NUM> are caster wheels so that the orientation of the wheels can be easily adjusted as necessary based on the movement of the driven wheels <NUM>. The front wheels <NUM> are thirty (<NUM>) centimeters in diameter and eighteen (<NUM>) centimeters in width, but other dimensions may be used for the front wheels <NUM> in other embodiments. Although the present disclosure describes the main rear wheels (driven wheels <NUM>) as driven wheels, depending on the configuration, any of the wheels may be "driven" by one or more motors. In this regard, the front wheels <NUM> and the anti-tip wheels <NUM> may be electrically powered in other embodiments.

In the illustrated embodiment, separate motors <NUM> (see <FIG>) may be used to control the amount of rotation at each driven wheel <NUM>. Thus, driven wheels <NUM> may be driven at different rates, and this may be beneficial to allow the wheelchair assembly <NUM> to easily rotate towards the left or to the right.

In the illustrated embodiment, the anti-tip wheels <NUM> may be elevated slightly above the ground so that the anti-tip wheels <NUM> will not contact the ground when the wheelchair assembly <NUM> is oriented in a typical upright manner. Further, the anti-tip wheels <NUM> may come in contact with the ground only when the wheelchair assembly <NUM> is rotated backward (e.g. clockwise in <FIG>). In this way, the anti-tip wheels <NUM> may prevent the wheelchair assembly <NUM> from tipping backward. However, in other embodiments, the anti-tip wheels <NUM> may be configured to contact the ground even when the wheelchair assembly <NUM> is in a typical upright orientation. The anti-tip wheels <NUM> may be beneficial to prevent the motors <NUM> (see <FIG>) from coming in contact with the ground - if the wheelchair assembly <NUM> begins to tip backward, the anti-tip wheels <NUM> may come in contact with the ground before the motors <NUM> (see <FIG>).

In the wheelchair assembly <NUM>, an input device <NUM> is provided at the end of an occupant armrest <NUM>. However, the input device <NUM> may be provided at other locations such as at the rear handle <NUM>, on the side of a seat frame <NUM>, on the back of the backrest frame <NUM>, on the motor subassembly <NUM> (see <FIG>), etc. The input device <NUM> may be used to provide inputs to control the operation of the wheelchair assembly <NUM>. The input device <NUM> may be connected to other electrical systems in the wheelchair assembly <NUM> so that inputs provided at the input device <NUM> may be executed by the electrical systems. For example, the input device <NUM> may be configured to receive user commands regarding the user's desired speed or direction for the wheelchair assembly <NUM>, and, based on the inputs received at the input device <NUM>, the operation of the motors <NUM> (see <FIG>) may be adjusted to change the speed of the driven wheels <NUM> or the direction of the wheelchair assembly <NUM>. The direction of the wheelchair assembly <NUM> may, for example, be changed by rotating the driven wheels <NUM> at different rotational speeds. The input device <NUM> includes a joystick <NUM> to receive user commands, however directional buttons and other components may be provided on the input device <NUM> as an additional or alternative way of inputting commands. The input device <NUM> may be configured to receive various commands - for example, the input device <NUM> may receive commands to operate in manual mode or electrically powered mode, to adjust maximum or minimum speeds, etc. The input device <NUM> may be part of an electronic control assembly that is configured to control motion of the wheelchair assembly <NUM>.

The wheelchair assembly <NUM> is an all-terrain wheelchair assembly. The front wheels <NUM>, the driven wheels <NUM>, and/or the anti-tip wheels <NUM> may be balloon tires, and the balloon tires may be configured to more easily traverse difficult terrains such as soft sand, hard sand, stony terrains, muddy terrains, and rocky terrains. In the illustrated embodiment of <FIG>, each of the front wheels <NUM>, the driven wheels <NUM>, and the anti-tip wheels <NUM> are balloon tires, whereas, in the illustrated embodiment of <FIG>, only the front wheels <NUM> and the driven wheels <NUM> are balloon tires. Notably, in the illustrated embodiment of <FIG>, the anti-tip wheels 220A are firm (e.g., traditional) wheels to aid in "digging" in to sand for increased traction. Where balloon tires are used, the balloon tires may be low-pressure balloon tires that are large, soft, and pliable in some embodiments, and these balloon tires may tend to float over sand compared to traditional wheels. A significant portion of the weight of the wheelchair assembly <NUM> may rest on the driven wheels <NUM>, and this may be beneficial to ensure that the driven wheels <NUM> have traction to drive the wheelchair assembly <NUM>. Balloon tires may greatly reduce the forces required to move the wheelchair assembly <NUM> across soft sand and other difficult terrains. Other traditional wheelchair assemblies often struggle to traverse soft sand and other difficult terrains and tend to get stuck in these difficult terrains. Thus, the wheelchair assembly <NUM> enables occupants to reach a larger number of areas as compared to more traditional wheelchair assembles.

While <FIG> illustrates one example wheelchair assembly, <FIG> illustrate varying perspective views of another example wheelchair assembly <NUM>. The wheelchair assembly <NUM> may include a seat subassembly <NUM> and a motor subassembly <NUM>. The wheelchair assembly <NUM> is configured to be easily assembled and disassembled, and the seat subassembly <NUM> and the motor subassembly <NUM> are configured to be selectively attached with each other to form the wheelchair assembly <NUM>. Different subassemblies within the wheelchair assembly <NUM> are selectively assembled and disassembled using toggle pins in the subassemblies. However, attachment of the subassemblies may be accomplished using other fasteners. Additionally, the seat subassembly <NUM> and the motor subassembly <NUM> are configured to be disassembled from each other so that they can be separately moved and carried by a single person. Once the subassemblies are disassembled, a user may easily move the seat subassembly <NUM> by resting the weight of the seat subassembly <NUM> on the front wheels <NUM>, and the user may easily move the motor subassembly <NUM> by resting the weight of the motor subassembly <NUM> on the driven wheels <NUM>. With the weight of the relevant subassembly on its wheels, the subassembly may be easily shifted and a reciprocal rotation of the wheels may be caused. Where the user is attempting to move the motor subassembly <NUM>, the user may be required to disengage a gearbox <NUM> (see <FIG>) in order to permit the driven wheels <NUM> to be freely rotated. Disassembly of the seat subassembly <NUM> and the motor subassembly <NUM> may permit these subassemblies to be fit into smaller volumes. For example, the two subassemblies may be stored together in a volume of less than <NUM> cubic feet, less than <NUM> cubic feet, less than <NUM> cubic feet, less than <NUM> cubic feet, or preferably less than <NUM> cubic feet. Thus, the subassemblies may be configured to fit in the trunk or boot of a vehicle such as an SUV.

The seat subassembly <NUM> may include the seat frame <NUM>, the backrest frame <NUM>, and the footrest frame <NUM>, and upholstery <NUM> (which may be provided on each of these frames to increase the comfort level for users). The backrest frame <NUM> may include rear handles <NUM> where an assistant may grasp the rear handles <NUM> to push the wheelchair assembly <NUM>. Furthermore, the backrest frame <NUM> may include occupant armrests <NUM>. These occupant armrests <NUM> may provide armrests for the occupant to rest his or her arms. The occupant armrests <NUM> are pivotable in the wheelchair assembly <NUM>. This may be beneficial to permit occupants to more easily exit the wheelchair assembly <NUM>. Furthermore, the pivotable nature of the occupant armrests <NUM> may make the backrest frame <NUM> more compact when stored. However, the occupant armrests may not be pivotable in other embodiments.

Furthermore, wheelchair assemblies may include various wheels. For example, the wheelchair assembly <NUM> may include front wheels <NUM>, driven wheels <NUM>, and anti-tip wheels 220A. As noted above, the illustrated anti-tip wheels 220A may not be balloon tires (and, instead, be traditional wheels). The driven wheels <NUM> may require balloon tires that are large in order for the wheels to effectively move in difficult terrains. The driven wheels <NUM> may possess a diameter of forty-nine (<NUM>) centimeters and a width of twenty-three (<NUM>) centimeters, but other sized driven wheels <NUM> may also be used. Rotation of the driven wheels <NUM> may be generated by motors <NUM> (see <FIG>) and the electrical components in the wheelchair assembly <NUM>. Further, the front wheels <NUM> and the anti-tip wheels 220A are not electrically powered and are permitted to adjust angular orientation and rotation speed based on adjustments at the driven wheels <NUM>. For example, the front wheels <NUM> are caster wheels so that the orientation of the wheels can be easily adjusted as necessary based on the movement of the driven wheels <NUM>. However, the front wheels <NUM> and the anti-tip wheels 220A may be electrically powered in other embodiments.

The wheelchair assembly may be an all-terrain wheelchair assembly. Thus, the wheelchair assembly may be configured to be used in more difficult environments such as beaches, which may have soft sand, dunes, and rocky terrain that is difficult to traverse. The front wheels <NUM> and the driven wheels <NUM> may each be balloon tires that are configured to more easily traverse difficult terrains such as soft sand, hard sand, stony terrains, muddy terrains, and rocky terrains. Further, the all-terrain nature of the wheelchair assembly <NUM> may require power where the wheelchair assembly <NUM> is electrically powered. Notably, relative to non-all-terrain wheelchairs, traversing over sand may require more power than other surfaces in urban environments such as pavement or hard floors. Where more power is needed, the electrically powered wheelchair assembly <NUM> may require larger motors and higher battery capacity. Thus, the motor <NUM> and the battery <NUM>' (see <FIG>) may be some of the heavier components in the wheelchair assembly <NUM>.

A battery box <NUM> may be provided in the seat subassembly <NUM>. More particularly, the battery box <NUM> is installed at the seat frame <NUM> underneath the location where the occupant sits. A battery <NUM>' (see <FIG>) may be provided within the battery box <NUM>, and the battery <NUM>' may have a weight of approximately fifteen (<NUM>) kilograms (although other weights are contemplated, such as less than <NUM> kilograms, less than <NUM> kilograms, less than <NUM> kilograms, etc.). Placement of the battery box <NUM> at the seat subassembly <NUM> may also tend to improve the weight distribution of the wheelchair assembly <NUM> as a whole by separating the heavier battery box <NUM> and the heavier components associated with the motor(s) <NUM> from each other (see e.g., <FIG>). Furthermore, the weight of the battery <NUM>' may be reduced by using lithium style batteries rather than traditional lead acid batteries. Notably, any type of battery may be used with various example embodiments described herein.

In some embodiments, the wheelchair assembly <NUM> may define a front-to-back direction, and the wheelchair assembly <NUM> may define a center of gravity. The motor subassembly <NUM> and the battery box <NUM> may each define a center of gravity. The center of gravity for the motor subassembly <NUM> may be provided rearwardly of the center of gravity for the wheelchair assembly <NUM> along the front-to-back direction. Further, the center of gravity for the battery <NUM> may be provided in front of the center of gravity for the wheelchair assembly <NUM> along the front-to-back direction. In some embodiments, the battery and the motors are separated by a horizontal distance of at least two hundred five (<NUM>) millimeters when the wheelchair assembly <NUM> is fully assembled and oriented in an upright position, and this may improve the weight distribution of the wheelchair assembly <NUM>. Improved weight distribution may be particularly important when the wheelchair assembly <NUM> is operating on an incline, as the incline may alter the typical orientation of the wheelchair assembly <NUM>.

Additionally, by placing the battery box <NUM> at the seat subassembly <NUM> rather than the motor subassembly <NUM>, the weight of the motor subassembly <NUM> may be reduced. In some embodiments, the weight of the seat subassembly <NUM> may be less than thirty-five (<NUM>) kilograms, and the weight of the motor subassembly <NUM> may be less than twenty-nine (<NUM>) kilograms. As a result, the wheelchair assembly <NUM> may be disassembled so that the seat subassembly <NUM> and the motor subassembly <NUM> are separated from each other, and each subassembly may be moved, carried or lifted individually by a single person. However, where a single person is uncomfortable carrying or lifting the subassemblies, a single person may still easily move the subassemblies to a storage location (e.g. a vehicle trunk or boot) and then the subassemblies may be easily carried or lifted into the storage location by two people. Notably, in some embodiments, the seat subassembly <NUM> and/or the motor subassembly <NUM> may be further broken down into easily attachable or mountable parts that further reduce weight of carriable parts. For example, the seat subassembly <NUM> may be broken down into a battery subassembly (that may be positionable within the battery box <NUM>), one or more front wheel assemblies (that each may be attachable to seat frame), a battery box subassembly, a backrest subassembly (that may include the backrest frame <NUM>), and/or other subassemblies. As another example, the motor subassembly <NUM> may be broken down into a motor platform subassembly, one or more anti-tip wheel subassemblies, one or more driven wheel assemblies, and/or other subassemblies. Further, the weight and volume of the motor subassembly may be significantly reduced by removing the driven wheels from the motor subassembly. Each subassembly may be easily carriable and attachable to each other to form the wheelchair assembly. In some embodiments, each subassembly may be less than thirty-five (<NUM>) kilograms.

Looking now at <FIG>, a connection arm <NUM> is illustrated. This connection arm <NUM> may help facilitate the connection between the motor subassembly <NUM> and the seat subassembly <NUM>. When the user wishes to operate the wheelchair assembly <NUM> without the motor subassembly <NUM> attached, the user may remove the motor subassembly <NUM> and the connection arm <NUM>. A rear axle 621A (see <FIG>) may be installed in place of the connection arm <NUM>, and rear wheels <NUM>' (see <FIG>) similar to the driven wheels <NUM> may be connected at both ends of the rear axle 621A.

<FIG> illustrates an enhanced perspective view of the example motor subassembly <NUM> where components within the motor subassembly <NUM> may be more easily seen. One or more motors <NUM> may be provided in order to generate rotation of the driven wheel hubs 218A and the driven wheels <NUM> that are attached to these driven wheel hubs 218A. In the illustrated embodiment, two motors <NUM> are provided, and each motor <NUM> is provided adjacent to a respective driven wheel <NUM> and is configured to generate rotation of the respective driven wheel <NUM>. Additional motors may be provided in other embodiments, and motors may be used at other locations. For example, in some embodiments, motors may be used to generate rotation of the front wheels or the anti-tip wheels, and the motors may be positioned adjacent to these wheels. Axles <NUM> may extend from a gearbox <NUM> (see <FIG>) and may engage with the driven wheels <NUM>.

The motor subassembly <NUM> may include a motor platform <NUM>. The motor platform <NUM> may provide a location where a top portion 238A of a motor controller box and a bottom portion 238B of a motor controller box may be attached. A motor controller may be provided in the motor controller box to control the operation of the motors <NUM>. Electrical wiring may extend from the motor controller to the battery box <NUM> (see <FIG>), to the input device <NUM> (see <FIG>), and to other electrical components. Motors <NUM> may be installed on the underside of the motor platform <NUM>. Positioning the motors <NUM> at this location may help prevent water or other materials projected from the front wheels <NUM> from coming into contact with the motors <NUM>, and the motors <NUM> may be provided proximate to the driven wheels <NUM> so provide a smaller footprint for the motor subassembly <NUM>.

The motor platform <NUM> may include arms <NUM> extending upwardly to connect with the backrest frame <NUM>. The arms <NUM> may be connected to mounting lugs 236A provided on the motor platform <NUM>. The arms <NUM> may be pivotable about an axis defined at the mounting lugs 236A (see <FIG>) so that the overall volume of the motor subassembly <NUM> may be reduced when the motor subassembly <NUM> is disassembled from the seat subassembly <NUM> (see <FIG>). Furthermore, the motor platform <NUM> may be connected to the connection arm <NUM> using one or more fasteners.

Additionally, anti-tip wheels 220A may be provided in the motor subassembly <NUM>. Arms <NUM> may extend rearwardly from the motor platform <NUM>, and the anti-tip wheels 220A may be connected to the arms <NUM>.

<FIG> illustrate varying perspective views of an example seat subassembly <NUM>. The seat subassembly <NUM> may include the seat frame <NUM>, the backrest frame <NUM>, and the footrest frame <NUM>. The seat subassembly <NUM> may connect to a connection arm <NUM> (see <FIG>) that is provided in the motor subassembly <NUM> (see <FIG>). The connection arm <NUM> may help facilitate a connection between the seat subassembly <NUM> and the motor subassembly <NUM> (see <FIG>). Where a user wishes to operate the wheelchair assembly <NUM> without the motor subassembly <NUM> attached, the user may remove the motor subassembly <NUM> and connect a rear axle 621A (see <FIG>) in place of the connection arm <NUM>, and rear wheels <NUM>' (see <FIG>) similar to the driven wheels <NUM> may be installed at both ends of the rear axle 621A using fasteners. A user may wish to operate the wheelchair assembly <NUM> proximate to water - where this is the case, the user may remove the motor subassembly <NUM> and other electronic components such as the input device <NUM> (see <FIG>) and the battery box <NUM> to avoid exposure of these electrical components to the water. However, electrical components may be protected with waterproof seals in some embodiments.

The connection arm <NUM> may possess features that help to position the seat subassembly <NUM> correctly relative to the motor subassembly <NUM> (see <FIG>). For example, protrusions 421B (see <FIG>) may extend upwardly from the connection arm <NUM> that guide the seat subassembly <NUM> to a correct position relative to the motor subassembly <NUM>. Furthermore, holes may be provided in the connection arm <NUM>, in the seat subassembly <NUM>, and at the motor subassembly <NUM> to help facilitate the connection between the two subassemblies.

While <FIG> illustrate a seat subassembly <NUM>, <FIG> illustrate varying perspective views of an example motor subassembly <NUM> that may be attached to the seat subassembly <NUM>. As illustrated, the motor subassembly <NUM> may include motors <NUM> and gearboxes <NUM> associated with motors <NUM>. A rear axle <NUM> may extend into each respective gearbox <NUM>, and the rear axle <NUM> may be received in a driven hub 218A. Thus, the motor <NUM> may operate in conjunction with the gearbox <NUM> to generate rotation of a rear axle <NUM>, and the rotation of the rear axle <NUM> may cause rotation of the attached driven hub 218A and the attached driven wheel <NUM>.

Further details regarding certain components of the example motor subassembly <NUM> may be seen in <FIG>. As illustrated in <FIG>, a motor controller box may be formed by a top portion 238A and bottom portion 438B. The top portion 238A and the bottom portion 438A may be effectively sealed against the motor platform <NUM> to make the controller box <NUM> waterproof and dustproof. This may be beneficial to protect certain electrical components and other components that may be sensitive to water, moisture, dust, or contamination.

Further details regarding the operation of the motor subassembly <NUM> may be seen in <FIG>. <FIG> illustrates an enhanced perspective view of an example driven wheel hub 218A, and <FIG> illustrates an enhanced perspective view of an example motor <NUM> and gear box <NUM>. The driven wheel hub 218A may be attached to the rear axle <NUM> so that the rear axle <NUM> and the driven wheel hub 218A rotate together. In some embodiments, rather than having a single rear axle <NUM> extending through both driven wheel hubs 218A, two separate rear axles <NUM> are provided, with a rear axle <NUM> being used with a respective driven wheel hub 218A. By providing separate rear axles <NUM>, the driven wheels <NUM> (see <FIG>) and the driven wheel hubs 218A may be rotated at different rotational speeds so that the wheelchair assembly may be permitted to rotate.

To install the motor subassembly <NUM> (see <FIG>) to the seat subassembly <NUM> (see <FIG>), any rear manual wheel subassembly <NUM> (see <FIG>) attached to the seat subassembly <NUM> may be removed. This may be done by removing any fasteners that are connecting the two subassemblies. With the rear manual wheel subassembly <NUM> being removed, the motor subassembly <NUM> may be provided in place of the rear manual wheel subassembly <NUM>. A user may position the seat subassembly <NUM> on the motor subassembly <NUM>, with the seat subassembly <NUM> resting on the connection bar <NUM> as illustrated in <FIG>. The protrusions 421B (see <FIG>) on the connection bar <NUM> may assist the user in positioning the seat subassembly <NUM> to expedite the assembly. Fasteners such as toggle pins may be used to secure the seat subassembly <NUM> to the connection bar <NUM> and/or other components of the motor subassembly <NUM>. Additionally, the arms <NUM> (see <FIG>) may also be rotated appropriately and attached to the seat subassembly <NUM>. To the extent a motor controller <NUM> (see <FIG>) is not already provided on the motor subassembly <NUM>, the motor controller <NUM> may be attached to the motor subassembly <NUM>. Furthermore, wiring may be extended from the motor controller <NUM> to other components on the seat subassembly <NUM> such as the battery box <NUM> (see <FIG>) and the input device <NUM> (see <FIG>). Wiring may also be extended from the motor controller <NUM> to the motors <NUM> (see <FIG>).

<FIG> illustrates a perspective view of an example battery box <NUM> disposed on the seat subassembly <NUM>. <FIG> illustrates a perspective view of an example bottom portion 230A of the battery box <NUM> of <FIG>. <FIG> illustrates a perspective view of an example top portion 230B of the battery box <NUM> of <FIG>. As illustrated, the battery box <NUM> may be disposed on the seat frame <NUM> (see <FIG>) of the seat subassembly <NUM>. The battery box <NUM> may be disposed directly underneath the seat 502A where an occupant will be positioned. The battery box <NUM> may be provided in front of the center of gravity for the wheelchair assembly <NUM> (see <FIG>), and this may be beneficial to evenly distribute the weight of the wheelchair assembly as the battery box <NUM> may counteract a moment generated by the motor subassembly. As illustrated in <FIG>, the bottom portion 230A of the battery box <NUM> may define an internal cavity. Furthermore, as illustrated in <FIG>, the top portion 230B of the battery box <NUM> may also define an internal cavity. When the bottom portion 230A and the top portion 230B are attached together, the two internal cavities of the two portions may define an internal volume where a battery <NUM>' (see <FIG>) may be stored. The bottom portion 230A and the top portion 230B may be attached together and sealed so that water, moisture, dust, and other contaminants are prevented from affecting the internal contents of the battery box <NUM> (e.g., the battery).

The seat subassembly <NUM> (see <FIG>) may include several different frames, and <FIG> illustrate various perspective view of these frames in isolation. <FIG> illustrates a perspective view of an example footrest frame <NUM>, <FIG> illustrates a perspective view of an example seat frame <NUM>, and <FIG> illustrates a perspective view of an example backrest frame <NUM>. The occupant armrest <NUM> may be pivotably attached to the remainder of the backrest frame <NUM>. Stops 208A may be provided on the backrest frame <NUM> to prevent rotation of an occupant armrest <NUM> past a deployed position. Frames may comprise lightweight material such as stainless steel or another lightweight metal. However, other materials may also be used in the frames.

Where a user desires to operate the wheelchair assembly without any motor subassembly attached, a rear wheel subassembly may be attached in place of the motor subassembly. <FIG> illustrates a perspective view of an example rear manual wheel subassembly <NUM>. The rear manual wheel subassembly <NUM> may include a rear axle 621A, and rear wheels <NUM>' may be attached at each end of the rear axle 621A. To attach the rear manual wheel subassembly <NUM>, the rear axle 621A may be installed at the same position as the connection arm <NUM> relative to the seat subassembly <NUM>. In some embodiments, the rear manual wheel subassembly <NUM> may be disassembled by removing fasteners in the form of toggle pins so that the rear wheels <NUM>' can be removed from the rear axle 621A.

Claim 1:
A wheelchair assembly (<NUM>, <NUM>) for easy assembly and disassembly, the wheelchair assembly comprising:
a plurality of frames (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
at least one motor (<NUM>);
a battery (<NUM>'); and
a plurality of wheels (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, 220A),
wherein the wheelchair assembly includes a plurality of subassemblies (<NUM>, <NUM>), wherein each of the plurality of subassemblies weighs less than thirty-five, <NUM>, kilograms, and wherein each of the plurality of subassemblies are configured to be selectively attached or disassembled with each other to form the wheelchair assembly.