Patent Publication Number: US-11643161-B2

Title: Mobility and exercise vehicle

Description:
PRIORITY CLAIM 
     This application is a continuation of, and claims priority from U.S. patent application Ser. No. 16/840,724, filed Apr. 6, 2020, now U.S. Pat. No. 11,447,204, which is a non-provisional of, and claims priority from, U.S. Provisional Patent Application Ser. No. 62/830,454, filed Apr. 7, 2019, the contents of each of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates generally to mobility vehicles. More particularly, this invention relates primarily to mobility vehicles such as wheelchairs and the like that are specially designed to provide increased mobility and therapy for handicapped individuals. 
     Related Art 
     Applicant is the inventor of U.S. Pat. Nos. 5,829,772; 6,179,314; 6,932,370; and 10,479,439, the contents of each of which are incorporated herein by reference in their entireties. Pump-Action vehicles have been used as children&#39;s toys and as therapy devices for children with disabilities, including learning or developmental disorders. They have also been proposed as transportation devices for adults. 
     Conventional wheelchairs can be bulky and difficult to operate. In particular, manually-operated wheelchairs include large driving wheels that can be cumbersome and difficult for many people to operate. They can also be difficult to position in relationship to furniture such as dining tables or other tables. Powered wheelchairs provide no exercise for the operator. Furthermore, conventional wheelchairs provide no mechanism for exercising a person&#39;s legs while operating. 
     What would be desirable is a mobility device that permits movement based on simple arm motions and provides enhanced convenience, comfort, accessibility, and movement to users of the mobility device, including handicapped persons. 
     SUMMARY OF THE INVENTION 
     According to various embodiments and principles of the present inventive concepts, a mobility vehicle can be provided having numerous improvements over the related art, including, for instance, a small footprint and tight turn radius, along with an improved driving system and increased therapeutic benefits. The mobility vehicle can also be easily transportable. 
     In particular, principles of the present inventive concepts provide a mobility vehicle that can be driven using simple arm motions such as a pumping or rowing action. This can provide a mobility assistance and exercise device for elderly, handicapped, or other mobility-restricted individuals. A pumper arm may be provided, for instance, which propels the vehicle through a simple pumping action. Alternatively, rowing arms may be provided which propel the vehicle based on a simple rowing action. A motor can also be provided to assist in providing movement. 
     A mobility vehicle according to principles of the present inventive concepts can further include one or more foot slides (or step plates) that engage the feet of the operator and slide forward and backward during operation of the pumper or rowing arms. The foot slide(s) may be mounted to a frame of the vehicle through sliding rails or other mechanisms that permit the slides to move forward and backward along the frame during operation of the vehicle. One or more sliding rails could be provided for the foot slide. Stops or limiters could be provided on the frame to limit the forward and rearward movement of the foot slide(s) along the rails. 
     In one embodiment, a foot slide is attached to the frame on two slide rails that permit the foot slide to slide smoothly forward and rearward. Stops are provided on the frame to limit the forward and rearward movement of the foot slide. The foot slide is preferably connected to a bottom end of the pumper arm. As the pumper arm is actuated, the foot slide moves forward and backward along the rails in opposition to the movement of the handle bar. More particularly, as the handle bar is pulled rearward (or backward toward the operator), the foot slide moves forward. As the handle bar is pushed forward, the foot slide moves rearward. 
     The foot slide can have one or more guards that help keep an operator&#39;s feet in position within the foot slide during operation. The guards could, for instance, be raised edges of the slide itself or other attached ridges or structures that keep the operator&#39;s feet from sliding out of the foot slide. The foot slide could include two, separate foot slides, one for each foot. Using the foot slide(s) connected to the pumper or rower arms, the operator&#39;s feet can move forward and rearward during operation of the vehicle and provide therapeutic exercise to the operator&#39;s legs. 
     When possible, the operator could also move the foot slide(s) themselves using their leg muscles to assist in the pumping action. The foot slide(s) can include a tread pattern and/or friction surface that helps maintain traction between the operator&#39;s feet and the foot slide. For instance, a tread pattern can be formed directly on the foot slide, or a rubberized or other gripping surface can be provided on top of the foot slide. 
     In an embodiment having two rower arms rather than a single pumper arm, two foot slides could be provided, each connected to an individual one of the rower arms. The foot slides in this embodiment move forward and rearward in opposition to the movement of the corresponding rower arm. 
     The pumper or rower arms may further connect to a steering mechanism of the vehicle through a universal joint located at the pivot point of the arms. The front wheel or wheels are preferably arranged on pivot pins that permit them to swivel right or left. A steering bar or steering bars are connected to the wheel(s) to cause them to pivot left or right on their pivot pins. A steering arm is preferably connected to the steering bar(s). The steering arm is connected to the pumper or rower arms through the universal joint. When the pumper or rowing arms are turned, the steering arm rotates in response and pivots the connected wheel(s) to turn the vehicle. 
     The pumper arm, for instance, may include a handle bar connected to a steering arm that extends downward between bracket-like structures arranged on opposite sides of the steering arm. A bottom end of the pumper arm is preferably connected to the foot slide. 
     In one embodiment, a mobility vehicle permits an operator to operate the vehicle using their arms and/or legs. Additionally, or alternatively, a battery-powered motor may provide all, a portion, or none of the driving force needed to operate the vehicle. A pumper arm assembly propels the mobility vehicle through a simple pumping action. A foot slide (or step plate) may engage the feet of the operator and slide forward and backward during operation of the pumper arm assembly. The foot slide may be mounted to a frame of the vehicle on sliding rails that permit the foot slide to slide forward and backward along the frame. Stops (or limiters) may be provided to limit the forward and/or rearward movement of the foot slide(s). A step plate support or reinforcement may also be provided which adds additional stability to the foot slide. 
     The foot slide may be connected to a bottom end of the pumper arm assembly through transfer arms and transfer linkages. The transfer linkages may be adjustable in length to finely tune the relationship between the pumper arm assembly and the foot slide. As the pumper arm is actuated, the foot slide moves forward and backward along the rails in opposition to the movement of the pumper arm handle bar. More particularly, as the handle bar moves backward, the foot slide moves forward. As the handle bar moves forward, the foot slide moves rearward. 
     The foot slide (step plate) can have one or more guards (not shown) that help keep an operator&#39;s feet in position within the foot slide during operation. The guards could, for instance, be raised edges of the slide itself or other attached ridges or structures that keep the operator&#39;s feet from sliding out of the foot slide. Using the foot slide connected to the pumper arm assembly, the operator&#39;s feet can move forward and rearward during operation of the vehicle and provide therapeutic exercise to the operator&#39;s legs even when they are not used to help provide the driving force. 
     The operator could, however, use their leg muscles to move the foot slide themselves to assist in the pumping action. The foot slide can include a tread pattern and/or friction surface (not shown) that helps maintain traction between the operator&#39;s feet and the foot slide. For instance, a tread pattern can be formed directly on the foot slide, or a rubberized or other gripping surface can be provided on top of the foot slide. 
     A steering assembly can be provided in which the pumper arm handle bar connects to a steering mechanism of the vehicle through a universal joint located at the pivot point of the pumper arm. The pumper arm assembly, for instance, may include a handle bar connected to a steering arm, with a bracket-like structured pumper arm that extends downward along opposite sides of the steering arm. A bottom end of the pumper arm is preferably connected to the foot slide through the transfer arms and transfer linkages. A hinge mechanism preferably connects the pumper arm to a pumper arm base that is, in turn, connected to the frame. 
     The front wheel is preferably mounted to the steering mechanism (in this embodiment, a steering fork), and the steering mechanism is arranged in such a way that it can swivel right and left with the front wheel. The steering arm may be connected to the steering mechanism through a steering bar. The steering arm may be connected directly to the handle bar or rower arms and then connected to the steering bar through the universal joint. When the handle bar is turned, the steering arm and steering bar rotate in response and pivot the steering mechanism, connected to the front wheel, to turn the vehicle. Bearings and bearing supports may be provided to align the steering arm and steering bar within the pumper arm and pumper arm base. 
     A battery powered motor and associated battery may be provided to assist in providing a driving force to the vehicle. The motor may be connected to the driving axle through a belt, chain, or other connection mechanism. In one embodiment, the operator is given the option of selecting how much assistance to receive from the motor. The selection may range anywhere from no assistance to maximum assistance. A sensor may also be provided that detects when the operator is having difficulty powering the vehicle and activates the motor assist in response. 
     In this embodiment, the driving mechanism may include a driving belt that travels in a loop around two wheels. A first, free spinning wheel is arranged toward the front of the vehicle. A second, drive wheel is fixidly attached to the driving axle, to force rotation of the driving axle in the direction of the rotation of the drive wheel. The belt and wheels could, of course, be readily replaced with a chain and sprockets. 
     A driving mechanism may be arranged over the belt and move forward and backward along with the foot slide in response to motion of the pumper arm. The driving mechanism may include a base, a bracket, and a driving catch that is pivotably mounted in the bracket. The driving catch may be biased by a spring into a forward driving position, or it may be activated into a forward driving position by a squeeze lever or other mechanism on the handle, or any other mechanical or electrically-assisted activation device. 
     In the forward driving position, a first engaging end of the driving catch engages with teeth in the belt. The first engaging end of the catch is designed such that it engages with the teeth of the belt when moving in a first (forward) direction, but slides past the teeth without engagement when moving in a second, opposite direction. In this manner, as the driving mechanism moves forward with the foot slide, the first engaging end of the catch engages with the teeth of the belt to drive the belt forward. As it does so, the drive wheel is driven forward, driving the axle (along with the connected rear wheels) in a forward direction as well. Thus, the mobility vehicle is driven forward in response to pumper arm assembly movement. 
     A reverse mechanism can also be provided that enables operation in a reverse direction. The reverse mechanism may operate by pivoting the driving member into a reverse position against the force provided by the spring. This can be accomplished, for example, using a squeeze handle arranged on the handle bar, or through the use of some other lever or switch that may be connected to the driving mechanism through cabling, for example. When the reverse mechanism is actuated, the driving member is pivoted such that an opposite, second engaging end of the driving member engages the belt. The second engaging end of the driving member is configured to engage teeth of the belt when moving in a rearward direction, but slide freely without engaging the belt when moving in a forward direction. In this manner, with the reverse mechanism engaged, the driving mechanism engages and drives the belt in a rearward direction, causing the rear drive wheel, axle, and rear wheels to move in a reverse direction. The vehicle is thus driven rearward in response to movement of the pumper arm and foot slide. The reverse mechanism can also be configured to cause the motor to drive the vehicle in the reverse direction. 
     In an alternative embodiment, two driving mechanisms can be provided to drive the belt or chain. This embodiment may be useful, for example, when rowing arms are used rather than a pumper arm. 
     In another embodiment, the driving mechanism may include a driving chain that travels in a loop around two sprockets. A first, free spinning sprocket is arranged near the front of the vehicle. A second, driving sprocket is fixidly attached to the driving axle, to force rotation of the driving axle in the direction of the rotation of the driving sprocket. 
     A forward driving catch may be arranged over the chain and move forward and backward along with the foot slide in response to motion of the pumper arm. The forward driving catch closes over the chain and catches and pulls on the top segment of the chain as it moves forward with the foot slide. As the top of the chain is driven forward, the rearward driving sprocket is also driven forward along with the axle and attached wheels. Thus, the mobility vehicle is driven forward in response to pumper arm movement. The forward driving catch may be configured to catch by default, or it may be activated by a squeeze lever or other mechanism on the handle, or any other mechanical or electrically-assisted activation device. In an embodiment with an activation mechanism, the forward driving catch may close over and catch the chain only when activated and the driving mechanism may be in a neutral position by default. 
     The forward driving catch may provide a ratchet-like action that catches and drives the chain forward during forward movement of the catch, but slides rearward freely without catching the chain. This can be accomplished, for instance, by providing engaging edges on the forward end of the catch that catch on the chain as the forward driving catch moves forward. The rearward end of the catch, however, can be open, or slanted away from the chain so that the forward driving catch slides freely rearward without engaging the chain. 
     A reverse mechanism can be provided in a similar manner. Specifically, a rearward driving catch can also be provided over a bottom segment of the chain and move forward and rearward along with the foot slide. The rearward driving catch may be activated by a squeeze handle or other activation device. When activated, the rearward driving catch closes over the chain and catches and pulls forward on the bottom of the chain as it moves forward with the foot slide as the pumper arm is pulled. As the bottom of the chain is pulled forward, the driving sprocket and driving axle are driven in reverse, causing rearward motion of the mobility vehicle. The forward driving catch should also be deactivated while the reverse driving catch is active. The reverse driving catch may have a ratchet-like construction similar to the forward driving catch such that it grabs and pulls the chain during forward movement, but slides freely along the chain during rearward movement. 
     In an alternative embodiment, the chain may be replaced by a belt or other driving system that circles around a free spinning front wheel or pulley and the rearward driving axle. The belt can be configured to provide the driving force to the axle, and the forward and rearward driving catches can be configured to pull the belt in a forward direction along the top or bottom of the belt, respectively, to drive the axle in the desired direction for forward or rearward movement of the vehicle. 
     In addition to the forward and rearward settings, a neutral setting may also be provided in which the foot slide and pumper arm do not engage the driving chain or belt. This setting may be provided to disable the pump-action power when a service provider desires to push or pull the vehicle without possible interference by the vehicle occupant, or when a vehicle occupant desires to coast without movement of the pumper arm or foot slide. 
     In another embodiment, the driving mechanism of the vehicle includes one or more sprockets arranged on an axle along with a drive wheel. The sprocket receives a chain connected to the pumper or rowing arms (such as through the foot slide) and rotates in response to the arm movement. Gears on the sprocket engage with a drive gear connected to the drive wheel to drive the drive wheel. 
     In a still further embodiment, two sprockets are provided on a driving assembly to selectively permit either forward or rearward movement of the vehicle based on pumper arm action. A first sprocket is connected to a forward driving gear, both of which are rotatably and slidably mounted on the axle on one side of the drive wheel. A second sprocket is connected to a rearward driving gear and both are rotatably and slidably mounted on the axle on an opposite side of the drive wheel from the first sprocket. The first and second sprockets drive their respective gears only in one direction (either forward or reverse, respectively) while spinning freely in the opposite direction. 
     A chain and spring assembly is provided for each of the sprockets. A first chain is arranged such that a first end of the first chain connects to the foot slide (or pumper arm). The first chain runs from the foot slide to a top of the first sprocket and then around the first sprocket. The second end of the first chain, coming from below the first sprocket, connects to one end of a first spring that is connected at its other end to the frame. As the pumper arm is actuated (pulled rearward), the foot slide moves forward, pulling the first chain along with it. As the first chain is pulled, it drives the first sprocket in a forward direction along with the connected forward driving gear and stretches the first spring. The first spring pulls the first chain back into its original position as the pumper arm moves forward again. 
     The second chain is arranged such that a first end of the second chain connects to one end of a spring that is connected at its other end to the frame. The chain extends from the spring to the top of the second sprocket and then around the sprocket. The second end of the second chain, coming from below the second sprocket, connects to the foot slide (or pumper arm). As the pumper arm is actuated, the second chain drives the second sprocket in a reverse direction along with its connected rearward driving gear. The second spring pulls the second chain back into its original position as the pumper arm moves forward again. 
     A chain retention system could be provided for one or both of the chains to reduce the length of spring needed to retract the chain to its original position. The chain retention system could include a pulley mounted on an end of a lever arm that is pivotably mounted to the frame. Rather than attach a spring to the end of the chain, a spring is attached to the lever arm such that the lever arm is biased in an extended position. The chain is connected to the frame at a first end near the chain retention system and extends around the pulley, to the sprocket, and then around the sprocket to the foot slide connection point. As the pump arm retracts and the foot slide moves forward, the chain pulls down on the pulley and lever arm and stretches the spring. When the pump arm moves forward, the spring pulls on the lever arm to raise it back into its extended position and return the chain to its starting position. 
     In this embodiment, a drive wheel hub may be rotatably mounted at a center location on the axle. A drive wheel gear may be rotatably arranged on the hub, and the drive wheel may be rigidly secured to the drive wheel gear to rotate along with the drive wheel gear. The drive wheel gear preferably includes teeth on both right and left side faces of the drive wheel gear. 
     The first and second sprockets may be connected to each other through the drive wheel hub using one or more pins or other mechanical connection that maintains them at a constant, predetermined distance from each other. The mechanical connection between the sprockets preferably maintains a constant distance between the first and second sprockets (with their associated gears) as they slide back and forth along the axle. One or more springs arranged on the axle preferably bias the sprockets in a position where the forward driving gear, connected to the first sprocket, engages a first side of the drive wheel gear arranged on the same side of the drive wheel as the first sprocket. With the forward driving gear engaged, the drive wheel is driven in a forward rotation as the pumper arm is operated, causing the vehicle to move forward. 
     A squeeze bar is preferably provided on one side of the pumper arm handle or one of the rowing-style handles. The squeeze bar may be connected to an actuator bar or shifting mechanism through a cable system. The actuator bar is preferably connected to the sprocket assembly. When the squeeze bar is squeezed, the cable tightens and activates the actuator arm or shifting mechanism to move the sprocket assembly. More particularly, in response to a squeeze of the squeeze bar, the actuator arm or shifting mechanism slides the sprocket assembly against the spring bias into a reverse position. The actuator arm may, for instance, be a curved rod or bar that communicates with the second sprocket. 
     The squeeze bar may, for instance, be configured such that a squeeze of ¾ inch or less is sufficient to move the sprocket assembly between its forward and reverse positions. As the sprocket assembly slides to the reverse position, the forward driving gear disengages from the drive wheel gear, and the rearward driving gear connected to the second sprocket engages with the drive wheel gear on the side opposite the forward driving gear. In this position, as the pumper arm is operated, the driving wheel is driven in a reverse direction, causing the vehicle to move backwards. 
     Of course, any other desired actuating mechanism (whether mechanical, electrical, or a combination of the two) such as a lever, button, dial, slide, or other device could be used to shift the sprockets from their forward-driving engagement to their rearward-driving engagement. Once the actuating or shifting mechanism is deactuated, the bias spring drives the first sprocket and forward driving gear back into engagement with the drive wheel gear and disengages the rearward driving gear so that operation of the pumper arm will drive the vehicle forward again. The teeth of the driving gears and drive wheel gear can be beveled or angled on their non-driving edges to permit self-alignment as the driving gears are moved into position. 
     A similar transmission system could also be employed on pedal and other vehicles to shift from forward to reverse. In an embodiment having two handles, such as a rowing-style design, an extra sprocket could be provided on each side of the drive wheel. The extra sprockets facilitate the opposing forward and backward movement of the two handles. 
     A braking system can also be provided. The braking system could include a braking bar that pushes against the drive wheel when the brake is actuated. The brake could be actuated using a squeeze lever arranged on a handle opposite to the reverse-actuating mechanism. The squeeze lever could be connected to the braking bar through a cabling system. When the brake squeeze lever is squeezed, the cable tightens and pulls the braking lever up against the drive wheel. The braking system could be lockable to lock the brake in place and keep the vehicle from moving. The brake locking system could, for instance, be a toggle type system in the squeeze lever or a separate latch that folds over the squeeze lever and locks it in place. Of course, the braking system could be actuated in any other desirable manner and include any other desired type of braking system. For instance, a hand lever connected to the frame could be used to actuate and release the brake. 
     The drive wheel may include an inflatable tire with a tread pattern mounted thereon and designed to engage a ground surface and provide sufficient traction to move the vehicle. The drive wheel may be arranged substantially directly underneath a seat of the vehicle (for instance, just rearward of a seat post) so that the operator&#39;s center of gravity is arranged substantially directly above the drive wheel. 
     The seat itself may be foldable, rotatable, lockable, and removable. More particularly, the seat back may fold down. The seat may swivel to permit easier operator entry and to facilitate positioning of the user next to a table. The seat may be lockable in a forward-facing position during operation of the vehicle and may be lockable in other desired positions as well. And the seat may be readily-removable by simply lifting it off of its seat post. The seat could also be lockably attached to the vehicle to prevent undesired removal. 
     In addition to the drive wheel with its inflatable tire, two additional wheels and tires may be provided on opposite ends of the rear axle to provide stability. In one embodiment, these stabilizing wheels are preferably free-spinning wheels having a hard rubber tire. Furthermore, the stabilizing tires may contain little or no tread. The tires on the driving wheel and stabilizing wheels preferably have approximately the same diameter to keep the vehicle from rocking from side to side during operation. 
     To further improve transportability of the vehicle, the entire front end of the vehicle (including for instance, the forward pumping and steering assembly) could be foldable to collapse against the frame of the vehicle. In one such embodiment, the front end assembly could be mounted to the rest of the frame through a hinged joint. A spring biased latch could be provided to mate within a bracket on the frame to securely hold the front end assembly in its operating position. To collapse the front end, the latch could be released using a release mechanism. The release mechanism could, for example, be a lever, button, dial, slide, or any other desired release mechanism. 
     In each of these embodiments, a small motor could be provided as an assistance mechanism to help propel the vehicle. In one embodiment, one or more sensors can be provided that sense resistance as an operator attempts to operate the pumper arms and propel the vehicle. If a large amount of resistance is detected (such as on an incline or for users with less arm mobility or strength), the sensors can detect this and engage the motor. The motor is preferably connected to the axle to help provide a driving force for the vehicle when needed. The motor may also be controllable to drive the axle in either a forward or reverse direction. 
     A user selectable switch or other user selectable control could be provided to enable the user to select how much assistance they would like from the motor. A user could, for example, choose to operate the vehicle completely manually, or the user could select up to a maximum amount of assistance from the motor. Preferably, the switch or other user selectable control permits a wide range of options between the minimum and maximum assistance. 
     Various aspects, embodiments, and configurations of the inventive concepts are possible without departing from the principles disclosed herein. The inventive concepts are therefore not limited to any of the particular aspects, embodiments, or configurations shown or described herein. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The foregoing and additional objects, features, and advantages of the present inventive concepts will become more readily apparent from the following detailed description, made with reference to the attached figures, in which: 
         FIG.  1    is a somewhat schematic perspective view of a mobility vehicle according to principles of the present inventive concepts; 
         FIG.  1 A  is a somewhat schematic exploded perspective view of the mobility vehicle of  FIG.  1   ; 
         FIG.  2    is a somewhat schematic perspective view of a pumper arm of the mobility vehicle of  FIG.  1   , according to additional principles of the present inventive concepts; 
         FIG.  2 A  is a somewhat schematic exploded perspective view of the pumper arm of  FIG.  2   ; 
         FIG.  3    is a somewhat schematic illustration of a belt drive assembly for the mobility vehicle of  FIG.  1   , according to one embodiment of the present inventive concepts; 
         FIG.  3 A  is a somewhat schematic illustration of the belt drive assembly of  FIG.  3   , illustrating operation in a reverse direction; and 
         FIG.  4    is a somewhat schematic illustration of a belt drive assembly according to an alternative embodiment. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     Various features, benefits, and configurations incorporating principles of the present inventive concepts in an illustrative embodiment are shown in the accompanying drawings. Additional features, benefits and configurations will be readily apparent to those of ordinary skill in the art based on this disclosure, and all such features, benefits and configurations are considered within the scope of the present invention. Various features will now be described in greater detail in connection with an embodiment of the present inventive concepts, as illustrated in the accompanying drawings. 
     Referring first to  FIGS.  1  and  2   , in one embodiment, a mobility vehicle  100  is provided which permits an operator to operate the vehicle  100  using their arms and/or legs. The vehicle  100  may additionally, or alternatively, provide leg and arm movement to the operator while operating using a battery-powered motor  122 . The battery-powered motor  122  may provide all, a portion, or none of the driving force needed to operate the vehicle  100 . In other words, the motor  122  may selectively provide the driving force for the vehicle  100 , assist in providing the driving force for the vehicle  100 , or be disabled from providing any assistance, dependent upon the needs or desires of the operator. 
     A pumper arm assembly  102  may be provided which propels the mobility vehicle  100  through a simple pumping action. A foot slide (or step plate) assembly  112  may also be provided which engages the feet of the operator and slides forward and backward during operation of the pumper arm assembly  102 . 
     More specifically, the foot slide assembly  112  may include one or more foot slides  114  mounted to a frame  150  of the vehicle  100  through slides  113   a  arranged on sliding rails  113 . The foot slide  114  may thereby be enabled to move forward and backward along the frame  150  during operation of the vehicle  100 . Stops or limiters (not shown) may be provided on the frame  150  or rails  113  to limit the forward and/or rearward movement of the foot slide  114  along the rails  113 . A step plate support or reinforcement  114   a  may also be provided which adds additional stability to the foot slide  114 . 
     The foot slide  114  may be connected to a bottom end of the pumper arm assembly  102  through transfer arms  110  and transfer linkages  111 . The transfer linkages  111  may be adjustable in length to finely tune the relationship between the pumper arm assembly  102  and the foot slide assembly  112 . As the pumper arm  104  is actuated, the foot slide  114  moves forward and backward along the rails  113  in opposition to the movement of the pumper arm handle bar  103 . More particularly, as the handle bar  103  moves backward, the foot slide  114  moves forward. As the handle bar  103  moves forward, the foot slide  114  moves rearward. 
     The foot slide (step plate)  114  can have one or more guards (not shown) that help keep an operator&#39;s feet in position within the foot slide  114  during operation. The guards could, for instance, be raised edges of the slide  114  itself or other attached ridges or structures that keep the operator&#39;s feet from sliding out of the foot slide  114 . Using the foot slide  114  connected to the pumper arm assembly  102 , the operator&#39;s feet can move forward and rearward during operation of the vehicle  100  and provide therapeutic exercise to the operator&#39;s legs even when they are not used to help provide the driving force. 
     The operator could, however, use their leg muscles to move the foot slide  114  themselves to assist in the pumping action. The foot slide  114  can include a tread pattern and/or friction surface (not shown) that helps maintain traction between the operator&#39;s feet and the foot slide  114 . For instance, a tread pattern can be formed directly on the foot slide  114 , or a rubberized or other gripping surface can be provided on top of the foot slide  114 . 
     Referring now additionally to  FIGS.  2  and  2 A , the pumper arm assembly  102  may include a pumper arm handle bar  103  that connects to a steering mechanism  109  of the vehicle  100  through a universal joint  105  located at the pivot point of the pumper arm  104 . The pumper arm assembly  102 , for instance, may include a handle bar  103  connected to a steering arm  106 , with a bracket-like structured pumper arm  104  that extends downward along opposite sides of the steering arm  106 . A bottom end of the pumper arm  104  is preferably connected to the foot slide  114  through transfer arms  110  and transfer linkages  111 . A hinge mechanism  107  connects the pumper arm  104  to the pumper arm base  104   a . The pumper arm base  104   a  may be connected to the frame  150 . 
     One or more wheels may be connected to the steering mechanism. In this embodiment, a single front wheel  130  is preferably mounted to the steering mechanism (in this embodiment, a steering fork)  109 , and the steering mechanism  109  is arranged in such a way that it can swivel right and left with the front wheel  130 . The steering arm  106  is preferably connected to the steering mechanism  109  through a steering bar  106   a . The steering arm  106  may be connected directly to the handle bar  103  or rower arms (not shown) and then connected to the steering bar  106   a  through the universal joint  105 . When the handle bar  103  is turned, the steering arm  106  and steering bar  106   a  rotate in response and pivot the steering mechanism  109 , connected to the front wheel  130 , to turn the vehicle  100 . Bearings  108  and bearing supports  108   a  may be provided to align the steering arm  106  and steering bar  106   a  within the pumper arm  104  and pumper arm base  104   a , respectively. A battery powered motor  122  and associated battery  121  may be included to assist in providing a driving force to the vehicle  100 . The motor  122  may be connected to the driving axle  200  through a belt, chain, or other connection mechanism. In one embodiment, the operator is given the option of selecting how much assistance to receive from the motor  122 . The selection may range anywhere from no assistance to maximum assistance. A sensor may also be provided that detects when the operator is having difficulty powering the vehicle and activates the motor assist in response. In some embodiments, the pumping or rowing action can be used to recharge the battery or batteries for the electrical motor. 
     Referring additionally to  FIGS.  3  and  3 A , an operation of the mobility vehicle  100 , according to this embodiment, will now be described in more detail. As illustrated in  FIGS.  3  and  3 A , in this embodiment, the driving mechanism  210  may be provided to drive a driving belt  206  that travels in a loop around two wheels  202 ,  204 . A first, free spinning wheel  202  may be arranged near the front of the vehicle  100 . And a second drive wheel  204  may be fixidly attached to the driving axle  200  to force rotation of the driving axle  200  in the direction of the rotation of the drive wheel  204 . Although this particular embodiment illustrates a belt  206  and wheels  202 ,  204 , those could readily be replaced with a chain and sprockets. 
     A driving mechanism  210  may be arranged over the belt  206  and move forward and backward along with the foot slide  114  in response to motion of the pumper arm  104 . The driving mechanism  210  may include a base  212 , a bracket  214 , and a driving catch  216  pivotably mounted in the bracket  214 . The driving catch  216  may be biased by a spring  218  into a forward driving position (as shown in  FIG.  3   ), or it may be activated into a forward driving position by a squeeze lever or other mechanism on the handle, or any other mechanical or electrically-assisted activation device (not shown). 
     Referring specifically to  FIG.  3   , in the forward driving position, a first engaging end  216   a  of the driving catch  216  engages with teeth in the belt  206 . The first engaging end  216   a  of the catch  216  is designed such that it engages with the teeth of the belt  216  when moving in a first (forward) direction, but slides past the teeth without engagement when moving in a second, opposite direction. In this manner, as the driving mechanism  210  moves forward with the foot slide  114 , the first engaging end  216   a  of the catch  216  engages with the teeth of the belt  206  to drive the belt forward. As it does so, the drive wheel  204  is driven forward, driving the axle  200  (along with the connected rear wheels  132 ) in a forward direction as well. Thus, the mobility vehicle  100  is driven forward in response to pumper arm assembly  102  movement. 
     Referring now to  FIG.  3 A , a reverse mechanism  211  can be provided that enables operation in a reverse direction by pivoting the driving member  216  against the force provided by the spring  218 . This can be accomplished, for example, using a squeeze handle  211 A (see  FIG.  2   ) on the handle bar  103 , or other lever or switch that may be connected to the driving mechanism  210  through cabling  211 B, for example. When the reverse mechanism  211  is actuated, the driving member  216  is pivoted such that an opposite, second engaging end  216   b  of the driving member  216  engages the belt  206 . The second engaging end  216   b  of the driving member  216  is configured to engage teeth of the belt  206  when moving in a rearward direction, but slide freely without engaging the belt teeth when moving in a forward direction. In this manner, with the reverse mechanism  211  engaged, the driving mechanism  210  engages and drives the belt  206  in a rearward direction, causing the rear drive wheel  204 , axle  200 , and rear wheels  132  to move in a reverse direction, thereby driving the vehicle  100  rearward, in response to movement of the pumper arm  104  and foot slide  114 . The reverse mechanism  211  can also be configured to cause the motor  122  to drive the axle in the reverse direction. 
     In an alternative embodiment shown in  FIG.  4   , two driving mechanisms  210 ,  210 A can be provided. This embodiment may be useful, for example, when rowing arms are used rather than a pumper arm. Each of the driving mechanisms  210 ,  210 A may operate in a manner similar to that described above. 
     Although not shown in the drawings, numerous other embodiments are possible without departing from the spirit and scope of the present inventive concepts. For example, in one embodiment, two sprockets may be provided on a driving assembly to selectively permit either forward or rearward movement of the vehicle based on pumper arm action. A first sprocket may be connected to a forward driving gear, and both the first sprocket and the driving gear may be rotatably and slidably mounted on the axle on one side of the drive wheel. A second sprocket may be connected to a rearward driving gear and both of these may be rotatably and slidably mounted on the axle on an opposite side of the drive wheel from the first sprocket. The first and second sprockets drive their respective gears only in one direction (either forward or reverse, respectively) while spinning freely in the opposite direction. 
     A chain and spring assembly may be provided for each of the sprockets. A first chain is arranged such that a first end of the first chain connects to the foot slide (or pumper arm). The first chain runs from the foot slide to a top of the first sprocket and then around the first sprocket. The second end of the first chain, coming from below the first sprocket, connects to one end of a first spring that is connected at its other end to the frame. As the pumper arm is actuated (pulled rearward), the foot slide moves forward, pulling the first chain along with it. As the first chain is pulled, it drives the first sprocket in a forward direction along with the connected forward driving gear and stretches the first spring. The first spring pulls the first chain back into its original position as the pumper arm moves forward again. 
     The second chain is arranged such that a first end of the second chain connects to one end of a spring that is connected at its other end to the frame. The chain extends from the spring to the top of the second sprocket and then around the sprocket. The second end of the second chain, coming from below the second sprocket, connects to the foot slide (or pumper arm). As the pumper arm is actuated, the second chain drives the second sprocket in a reverse direction along with its connected rearward driving gear. The second spring pulls the second chain back into its original position as the pumper arm moves forward again. 
     A chain retention system can be provided for one or both of the chains to reduce the length of spring needed to retract the chain to its original position. The chain retention system could include a pulley mounted on an end of a lever that is pivotably mounted to the frame. Rather than attach a spring to the end of the chain, a spring is attached to the lever such that the lever is biased in an extended position. The chain is connected to the frame at a first end near the chain retention system and extends around the pulley, to the sprocket and then around the sprocket to the foot slide connection point. As the pump arm retracts and the foot slide moves forward, the chain pulls down on the pulley and lever and stretches the spring. When the pump arm moves forward, the spring pulls back on the lever to raise it back into its extended position and return the chain to its starting position. 
     A drive wheel hub is rotatably mounted at a center location on the axle. A drive wheel gear is rotatably arranged on the hub, and the drive wheel is rigidly secured to the drive wheel gear to rotate along with the drive wheel gear. The drive wheel gear preferably includes teeth on both right and left side faces of the drive wheel gear. 
     The first and second sprockets may be connected to each other through the drive wheel hub using one or more pins or other mechanical connection that maintains them at a constant, predetermined distance from each other. The mechanical connection between the sprockets maintains the constant distance between the first and second sprockets (with their associated gears) as they slide back and forth along the axle. One or more springs arranged on the axle preferably bias the sprockets in a position where the forward driving gear connected to the first sprocket engages a first side of the drive wheel gear arranged on the same side of the drive wheel as the first sprocket. An inflatable rubber tire may be arranged on the drive wheel to engage with a travel surface. With the forward driving gear engaged, the drive wheel is driven in a forward rotation as the pumper arm is operated, causing the vehicle to move forward. 
     A squeeze bar is preferably provided on one side of the pumper arm handles. The squeeze bar may be connected to an actuator arm (or other shifting mechanism) through a cable system. The actuator bar is preferably connected to the sprocket assembly. When the squeeze bar is squeezed, the cable tightens and activates the actuator arm to move the sprocket assembly. More particularly, in response to a squeeze of the squeeze bar, the actuator arm slides the sprocket assembly against the spring bias into a reverse position. The actuator arm may, for instance, be a curved rod that communicates with the second sprocket. The squeeze bar may, for instance, be configured such that a squeeze of ¾ inch or less is sufficient to move the sprocket assembly between its forward and reverse positions. 
     In one aspect, the squeeze bar pulls a cable connected to a shifting mechanism. As the cable tightens, the shifting mechanism moves forward. The shifting mechanism is mounted on the axle near the second sprocket and has a narrow portion, a wide portion, and a curved slide surface between the narrow and wide portion. In the biased position, the narrow portion sits between the second sprocket and an axle mount. As the shifting mechanism moves forward, it slides such that the wider portion is slid into position between the axle mount and the second sprocket, pushing the sprocket assembly into the reverse position. 
     As the sprocket assembly slides to the reverse position, the forward driving gear disengages from the drive wheel gear, and the rearward driving gear connected to the second sprocket engages with the drive wheel gear on the side opposite the forward driving gear. In this position, as the pumper arm is operated, and the drive wheel is driven in a reverse direction, causing the vehicle to move backwards. 
     Of course, any other desired actuating mechanism such as a lever, button, dial, slide, or other device could be used to shift the sprockets from their forward-driving engagement to their rearward-driving engagement. Once the actuating (or shifting) mechanism is deactuated, the bias spring drives the first sprocket and forward driving gear back into engagement with the drive wheel gear and disengages the rearward driving gear so that operation of the pumper arm will drive the vehicle forward again. The teeth of the driving gears and drive wheel gear can be beveled or angled on their non-driving edges to permit self-alignment as the driving gears are moved into position. 
     A braking system can also be provided. The braking system could include a braking bar that pushes against the drive wheel when the brake is actuated. The brake could be actuated using a squeeze lever arranged on a handle opposite to the reverse-actuating mechanism. The squeeze lever could be connected to the braking bar through a cabling system. When the brake squeeze lever is squeezed, the cable tightens and pulls the braking lever up against the drive wheel. The braking system could be lockable to lock the brake in place and keep the vehicle from moving. The brake locking system could, for instance, be a toggle type system in the squeeze lever or a separate latch that folds over the squeeze lever and locks it in place. Of course, the braking system could be actuated in any other desirable manner and include any other desired type of braking system. For instance, a hand lever connected to the frame could be used to actuate and release the brake. 
     The drive wheel could include an inflatable tire mounted thereon with a tread pattern designed to engage a ground surface and provide sufficient traction to move the vehicle. The drive wheel may be arranged substantially directly underneath a seat of the vehicle (for instance, just rearward of a seat post) so that the operator&#39;s center of gravity is arranged substantially directly above the drive wheel. 
     The seat itself may be foldable, rotatable, lockable, and removable. More particularly, the seat back may fold down. The seat may swivel to permit easier operator entry and to facilitate positioning of the user next to a table. The seat may be lockable in a forward-facing position during operation of the vehicle and may be lockable in other desired positions as well. And the seat may be readily-removable by simply lifting it off of its seat post. The seat could also be lockably attached to the vehicle to prevent undesired removal. 
     In addition to the driving wheel and inflatable tire, two additional wheels and tires may be provided on opposite ends of the rear axle to provide stability. In one embodiment, these stabilizing wheels are preferably free-spinning wheels having a hard rubber tire. Furthermore, the stabilizing tires may contain little or no tread. The tires on the driving wheel and stabilizing wheels preferably have approximately the same diameter to keep the vehicle from rocking from side to side during operation. 
     To further improve transportability of the vehicle, the entire front end of the vehicle (including for instance, the forward pumping and steering assembly) could be foldable to collapse against the frame of the vehicle. In one such embodiment, the front end assembly could be mounted to the rest of the frame through a hinged joint. A spring biased latch could be provided to mate within a bracket on the frame to securely hold the front end assembly in its operating position. To collapse the front end, the latch could be released using a release mechanism. The release mechanism could, for example, be a lever, button, dial, slide, or any other desired release mechanism. 
     In another alternative embodiment, rower arms can be provided rather than a single pumper arm. In such an embodiment, two foot slides could be provided, each connected to an individual one of the rower arms. The foot slides in this embodiment move forward and rearward in opposition to the movement of the corresponding rower arm. In an embodiment having two handles, such as a rowing-style design, an extra sprocket could be provided on each side of the drive wheel. The extra sprockets facilitate the opposing forward and backward movement of the two handles. 
     In a still further embodiment, the driving mechanism may include a driving chain that travels in a loop around two sprockets. A first, free spinning sprocket is arranged near the front of the vehicle. A second, driving sprocket is fixidly attached to the driving axle, to force rotation of the driving axle in the direction of the rotation of the driving sprocket. 
     A forward driving catch may be arranged over the chain and move forward and backward along with the foot slide in response to motion of the pumper arm. The forward driving catch may be activated by a squeeze lever or other mechanism on the handle, or any other mechanical or electrically-assisted activation device. When activated, the forward driving catch closes over the chain and catches and pulls on the top segment of the chain as it moves forward with the foot slide. As the top of the chain is driven forward, the rearward driving sprocket is also driven forward along with the axle and attached wheels. Thus, the mobility vehicle is driven forward in response to pumper arm movement. 
     The forward driving catch preferably provides a ratchet-like action that catches and drives the chain forward during forward movement of the catch, but slides rearward freely without catching the chain. This can be accomplished, for instance, by providing engaging edges on the forward end of the catch that catch on the chain as the forward driving catch moves forward. The rearward end of the catch, however, can be open, or slanted away from the chain so that the forward driving catch slides freely rearward without engaging the chain. 
     A reverse mechanism can be provided in a similar manner. Specifically, a rearward driving catch can also be provided over a bottom segment of the chain and move forward and rearward along with the foot slide. The rearward driving catch may be activated by a squeeze handle or other activation device. When activated, the rearward driving catch closes over the chain and catches and pulls forward on the bottom of the chain as it moves forward with the foot slide as the pumper arm is pulled. As the bottom of the chain is pulled forward, the driving sprocket and driving axle are driven in reverse, causing rearward motion of the mobility vehicle. The reverse driving catch may have a ratchet-like construction similar to the forward driving catch such that it grabs and pulls the chain during forward movement, but slides freely along the chain during rearward movement. 
     In an alternative embodiment, the chain may be replaced by a belt or other driving system that circles around a free spinning front wheel or pulley and the rearward driving axle. The belt can be configured to provide the driving force to the axle, and the forward and rearward driving catches can be configured to pull the belt in a forward direction along the top or bottom of the belt, respectively, to drive the axle in the desired direction for forward or rearward movement of the vehicle. 
     In addition to the forward and rearward settings, a neutral setting may also be provided in which the foot slide and pumper arms do not engage the driving chain or belt. This setting may be provided to disable the pump-action power when a service provider desires to push or pull the vehicle without possible interference by the vehicle occupant, or when a vehicle occupant desires to coast. 
     Various other designs and embodiments are also contemplated and numerous variations to the specific designs identified above are possible without departing from the spirit and scope of the inventive concepts. For instance, the belt or chain could be a belt, chain, rope, cable, or any other structure or material that wraps around the pulleys or gears. The driving mechanism could have a gripper, actuator, or catch on one or both sides of belt, chain, rope, cable, or other material. If arranged on both sides, the mechanisms could be configured to catch on opposite sides and move in opposite directions. Having described and illustrated principles of the present inventive concepts on in various preferred embodiments thereof, it should be apparent that the invention can be modified in arrangement and detail without departing from such principles.