Transport chair for a patient

Information

  • Patent Grant
  • 6793232
  • Patent Number
    6,793,232
  • Date Filed
    Friday, December 5, 2003
    21 years ago
  • Date Issued
    Tuesday, September 21, 2004
    20 years ago
Abstract
Disclosed is a wheelchair for a patient comprising a support frame, at least two main wheels mounted on sides of the support frame and a seat base disposed upon the support frame. Alternatively, a stretcher topping may be mounted upon a laterally slidable storage compartment that may be affixed to the support frame. The stretcher topping includes a seat base assembly having a removable seat panel stacked upon a potty panel with an aperture formed therethrough and opening into the storage compartment. The potty panel allows for evacuation of the patient while resting in the wheelchair. The seat base and the stretcher topping are configured for selectively raising and lowering the patient between first and second levels. At least one security beam is disposed on the wheelchair and may be configured as a hand hold for steadying the patient when transferring onto and off of the seat base.
Description




STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT




(Not Applicable)




BACKGROUND OF THE INVENTION




The present invention pertains generally to wheelchairs and, more particularly, a uniquely configured wheelchair specifically adapted for transferring a physically challenged patient into and out of the wheelchair under the patient's own power or with the assistance of no more than one person.




There exists in the prior art, wheelchairs that are configured to provide some degree of mobility to non-ambulatory or physically challenged patients. Some of these patients are confined to a wheelchair due to a variety of conditions including progressive neurological degeneration wherein the patient may be unable to move without the combined efforts of at least two people to lift the patient into and out of the wheelchair. For example, it may be desirable to relocate the patient from a bed in a bedroom to a living room chair in a living room. Unable to move under their own power due to lack of balance or muscular strength, the patient must be physically lifted from the bed, placed into the wheelchair, wheeled into the living room, and then lifted again out of the wheelchair and into the living room chair.




The lifting usually must be performed by two people or caregivers possessing sufficient strength, as one caregiver may not possess sufficient strength. In addition, the patient typically cannot be without a caregiver for more than six hours per day. Furthermore, the patient may require the assistance of a caregiver during the night in order to utilize bathroom facilities. Nursing homes may provide the assistance of caregivers who are specifically employed and trained to move nursing home patients.




Such caregivers in nursing homes can lift and move the patient at various times during the day and night, as needed. However, the cost of nursing homes is prohibitively expensive. The high cost of nursing homes and hospitals may not be covered under government health care plans or private health care insurance. Employing a full-time live in caregiver is equally expensive. In addition, insurance costs may prohibit live-in caregivers and nursing home caregivers from moving the patient outside the confines of the patient's home or the nursing home.




A few wheelchairs of the prior art are configured such that the patient does not have to be lifted out of the wheelchair in order to use the toilet or take a shower. Such wheelchairs include a seat panel having a potty dish formed therewith such that the patient may evacuate without the need to transfer the patient to a bathroom. However, such wheelchairs having a potty dish included with the seat panel suffer from several deficiencies that detract from the overall utility of the wheelchair. For example, because the potty dish is integral with the seat panel, the seat panel must be cleaned after each use.




In attempts to overcome the above mentioned limitations, electric wheelchairs have been developed. These electric wheelchairs include options such as powered seats that operate in a manner similar to the powered seats available in many automobiles. These powered seats may include a seat height adjustment capability that allows the patient to be raised above the level of an object to which the patient may be transferred. The lifting capability of the powered seats partially solves the lifting problem in that the need for two caregivers to lift the patient is eliminated.




However, powered wheelchairs may cost many thousands of dollars and thus may be unaffordable to the same people unable to afford the high cost of nursing homes. Furthermore, for patients having a diminished sense of balance, the gap between the wheelchair and the article to which the patient is to be moved presents another challenge in that the patient may not be able to transfer across the gap. A loss of balance while the patient is traversing the gap could be disastrous if a lone caregiver does not posses sufficient strength to steady the patient during the transfer.




Thus, there exists a need in the art for a wheelchair possessing the capability to raise the patient above the level of the article to which the patient may be transferred. Also, there exists a need in the art for a wheelchair capable of being lowering to a level that is less than that of the article from which the patient may be transferred. Additionally, there exists a need in the art for a wheelchair that provides the patient with the ability to steady and maintain their balance when transferring into and out of the wheelchair. Also, there exists a need in the art for a wheelchair that provides resistance from tipping over when the patient transfers into and out of the wheelchair. Furthermore, there exists a need in the art for a wheelchair that allows the patient to evacuate without transferring the patient to bathroom facilities. Finally, there exists a need in the art for a wheelchair that allows for easy cleanup after patient evacuation.




BRIEF SUMMARY OF THE INVENTION




The present invention specifically addresses and alleviates the above referenced deficiencies associated with wheelchairs. More particularly, the present invention is a uniquely configured wheelchair specifically adapted for transferring a patient into and out of the wheelchair by providing a combination of a selectively movable seat base with at least one security beam disposed on the wheelchair. The seat base is configured for selectively raising or lowering a patient between a first level and a second level such that the patient may be initially placed at a higher level than the article to which they are to be transferred. The patient then grabs the security beam for stability and balance and simultaneously moves downward and laterally to perform the transfer. In this manner, the force of gravity may be utilized to advantage so that the patient, either acting alone or with assistance, may easily transfer from the wheelchair to another location such as a living room chair or sofa, bathroom facilities or the passenger seat of an automobile, with the aid of no more than a single caregiver.




The wheelchair is comprised of a support frame to which is attached at least two main wheels, the seat base and at least one security beam. Additional components may include a pair of transit wheels, a pair of arm rests, a seat back and a head rest. As was mentioned above, the seat base is configured for selectively raising and lowering the patient between the first level and the second level as may be facilitated through various lifting mechanisms. The wheelchair may comprise a pair of anti-tip booms to prevent tipping during use of the security beams in patient transfers, as will be discussed in detail below.




A pair of transit wheels may be provided. The transit wheels may be mounted to the support frame and configured to be freely swivelable, providing lateral and forward/aft stability as well as steering capability to the wheelchair during normal operation. In comparison, the anti-tip booms provide lateral and forward/aft stability to prevent tipping of the wheelchair when the patient's weight is placed on the security beams during transfers into and out of the wheelchair. Thus, the distance between the main wheels and the respective ends of the anti-tip booms is fairly long as compared to the relatively short distance between the main wheels and the transit wheels.




The support frame has a front, a rear, and opposing sides with the front facing in a forward direction and the rear facing in an aft direction. The opposing sides of the support frame face in opposing lateral directions. The main wheels are mounted on the support frame and may be mounted on either side of the support frame. The seat base is disposed upon the support frame between the main wheels and is configured for selectively raising and lowering the patient between the first level and the second level. The lifting mechanism may comprise a scissors jack, a pneumatic or hydraulic jack or any number of alternative devices. The lifting mechanism may be configured for lowering the seat base to the first level such that the patient may be lifted off of the floor with the aid of the security beams. In such a scenario, the security beams may be horizontally oriented and slipped under the armpits of the patient in order to lift the patient up to a height sufficient for transfer into the wheelchair or into an adjacently located article of furniture.




The security beams may be substantially horizontally orientated and may project outwardly in the forward direction. The wheelchair may include only a single security beam or the pair of security beams disposed adjacent each of the main wheels. The security beams may alternatively have a substantially vertical orientation. The security beams


26


may be of a length such that they extend sufficiently past the wheelchair such that the patient sitting on an adjacent article of furniture may easily grasp the security beam prior to transferring into the wheelchair. The security beams may be axially extendable, such as by means of a telescoping configuration, such that the overall length may be adjusted beyond an initial length. The security beam may be configured to be pivoted and locked into any position intermediate the substantially vertical orientation and the substantially horizontal orientation.




If a seat back and head rest are included with the wheelchair, the seat back may be reclinable and pivotable between any positions intermediate a generally upright and a reclined position. The head rest, normally disposed above the seat back, may be configured to be detachable from the seat back such that it may be removed. A pair of arm rests may be included, the arm rests projecting in the lateral direction and disposed above each side of the seat base. The arm rests may be temporarily pivoted out of the way or they may be altogether removed from the seat back to further facilitate the patient transfer. The wheelchair may include the anti-tip booms disposed on either side of the support frame and they may be horizontally oriented and projecting in the forward direction




The anti-tip booms may be extended in the forward direction in order to provide stability for the wheelchair against tipping such as when the weight of the patient is placed upon the security beam. The anti-tip booms may be configured to project into one of the opposing lateral directions in order to prevent tipping of the wheelchair when the patient is transferring into and out of the side of the wheelchair. The anti-tip booms may include caster wheels mounted on the end of the anti-tip booms that are held a few inches above the floor when the anti-tip booms are retracted but are placed into contact with the floor once the anti-tip booms are extended.




In operation, the wheelchair functions as a conventional wheelchair once the patient is seated therein. However, the wheelchair advantageously includes the additional combined features of the selectively moveable seat base and the security beams for allowing the patient to transfer from an article of furniture to the wheelchair, or vice versa, utilizing the force of gravity. For example, during a transfer of the patient from a bed to the wheelchair, the wheelchair is moved adjacent the bed. The security beam is disposed in a horizontal orientation and axially extended in order that the patient may conveniently grasp the security beam prior to the transfer. The patient can then use the security beams as a portable banister or hand rail to enable use of the patient's hand, arm and upper-torso muscles.




The patient is then laterally moved toward the seat base while the force of gravity acts to simultaneously pull the patient down toward the seat base. If unable to move laterally under their own power, the patient may be assisted. The anti-tip booms may be extended to any length and may be pivoted into the forward-facing or lateral-facing directions in order to provide stability against tipping of the wheelchair as may otherwise occur during application of the patient's weight upon the security beam. The patient can then be wheeled about under their own power or with assistance in the conventional manner. Transfer of the patient out of the wheelchair and into an article of furniture, such as a living room chair, is accomplished in the reverse order as that described above for transfer of the patient into the wheelchair.




The wheelchair may also be provided in a second embodiment wherein a stretcher topping may be disposed on a storage compartment which is slidably mounted on the support frame. Advantageously, the combination storage compartment and stretcher topping of the second embodiment and the seat base of the first embodiment are each configured such that they may be interchanged with each other so that the user is provided with two options for supporting the patient. The stretcher topping of the second embodiment is comprised of the storage compartment, a seat base assembly, a reclinable seat back and a leg support. The seat base assembly includes potty capabilities for the patient due to the inclusion of a potty panel disposed underneath a forward part of the seat panel. Advantageously, the stretcher topping may be arranged in a planar, stretcher-like configuration allowing the patient to lie in a supine or prone position. In addition, the stretcher topping may be arranged in a seated configuration wherein the seat back is positioned into a reclined orientation with the leg support extending downwardly in an angled orientation from the seat base assembly. The leg support may be removed.




The storage compartment of the wheelchair of the second embodiment is laterally slidably mounted upon the support frame with the seat base assembly being mounted upon the storage compartment. By configuring the storage compartment to be laterally slidable in combination with its height adjustability between first and second levels, the stretcher topping may be positioned in any position relative to an article to or from which the patient may be transferred. The stretcher topping is configured such that it may also be laterally slid over one of the main wheels for close placement near the patient to reduce any gap that may otherwise exist between the stretcher topping and the article. Gravity may be used to assist in the transfer of the patient between the stretcher topping and the article wherein the stretcher topping may be positioned such that it is lower than the article from which the patient is to be transferred. Conversely, the stretcher topping may be positioned such that it is higher than the article to which the patient is to be transferred.




The wheelchair of the second embodiment shares a commonality with several components of the wheelchair of the first embodiment including the support frame, the two main wheels, and the pair of transit wheels. The storage compartment is mounted on the support frame with a pair of sliding mechanisms interposed between the storage compartment and the support frame. The storage compartment may include a vertically disposed divider panel to divide the storage compartment into a forward section and an aft section. The aft section may include a removable drawer for holding various items. The drawer may be slidably advanced into and withdrawn from the aft section similar to the operation of a clothes dresser drawer. The seat base assembly is comprised of a removable seat panel and a potty panel. The seat panel may be sized and configured such that it is stackable upon and removable from the similarly sized potty panel. The potty panel has an aperture formed therethrough that opens into the aft section of the storage compartment. During use of the potty panel, the seat panel is temporarily removed to expose the potty panel.




The stretcher topping includes the seat back which is configured to be reclinable such that it may be positioned at any orientation between and including generally horizontal and vertical orientations. The seat back may be folded on top of the seat base assembly in order to reduce the size of the wheelchair. Arm rests may also be included with the wheelchair and each may be removable in a manner similar to the arm rest of the first embodiment and may further be vertically and/or laterally pivotably attached to the seat back such that they may be folded down flat.




A removable leg support may be included with the stretcher topping and may be pivotable about the forward end of the seat base between and including substantially horizontal and vertical orientations similar to that described above for the seat back. The leg support may include an outwardly pivotable or foldable foot rest which may be configured such that it may fold down against the leg support to allow the patient's legs to extend outstretched on the stretcher topping. The wheelchair of the second embodiment may further include at least one security beam configured as a hand-hold to aid the patient in transfers to and from the wheelchair. The security beams may be disposed behind the seat back by plugging into a security beam socket mounted behind the seat back and interposed between the main wheels. The security beams may be configured to be pivotable between substantially vertical and horizontal orientations and may be extendable outwardly from the wheelchair.




The anti-tip booms may be included with the wheelchair to prevent tipping when the weight of the patient is concentrated on an end or side of the stretcher topping. Each one of the anti-tip booms may be substantially horizontally disposed adjacent one of the main wheels and may be configured to be axially extendable and project outwardly from the support frame. The wheelchair of the second embodiment may further include a lifting mechanism configured for selectively raising or lowering the storage compartment and, hence, the stretcher topping between the first level and the second level.











BRIEF DESCRIPTION OF THE DRAWINGS




These as well as other features of the present invention will become more apparent upon reference to the drawings wherein:





FIG. 1

is a perspective view of a wheelchair in a first embodiment of the present invention illustrating the arrangement of a pair of security beams and a pair of anti-tip booms disposed adjacent a pair of main wheels;





FIG. 2

is a side elevational view of the wheelchair illustrating the security beams disposed in a horizontal orientation;





FIG. 3

is a plan view of the wheelchair taken along line


3





3


of

FIG. 2

illustrating the anti-tip booms disposed in laterally outwardly projecting orientations;





FIG. 4

is plan view of the wheelchair illustrating the security beams projecting outwardly in a horizontal orientation with the seat base of the wheelchair being raised to a second level;





FIG. 5

is a side elevational view of the wheelchair illustrating the security beams being disposed in a vertical orientation;





FIG. 6

is a partial side elevational view of the wheelchair illustrating arm rests of the wheelchair being raised upwardly such that they may be pivoted laterally outwardly;





FIG. 7

is a partial plan view of the wheelchair illustrating the seat base being disposed laterally over a main wheel with the arm rests being disposed in an outwardly pivoted orientation;





FIG. 8

is a partial side elevational view of the wheelchair illustrating a seat back of the wheelchair being pivoted into a reclining orientation;





FIG. 9

is a perspective view of the wheelchair illustrating a winch motor, a winch pulley mounted on the security beam, and a winch cable connected to a patient via a body harness for raising and lowering the patient;





FIG. 10

is a perspective view of the wheelchair with small-diameter main wheels and illustrating the seat base lowered to a first level;





FIG. 11

is a perspective view of the wheelchair of the first embodiment illustrating the seat base raised to the second level and illustrating the lifting mechanism configured as a scissors jack;





FIG. 12

is a side elevational view of the wheelchair in a second embodiment having a stretcher topping mounted upon a laterally slidable storage compartment;





FIG. 13

is a exploded partial side view of a leg support removably attachable to a seat base assembly of the wheelchair of the second embodiment;





FIG. 14

is a exploded partial perspective view of the seat base assembly and the laterally slidable storage compartment mountable on a pair of sliding mechanisms;





FIG. 15

is a plan view of the wheelchair of the second embodiment illustrating the feature of the storage compartment having a forward section and an aft section with a drawer that may be slidably inserted thereinto;





FIG. 16

is side elevational view of the wheelchair of the second embodiment illustrating the security beam mounted on an arm rest; and





FIG. 17

is side elevational view of the wheelchair of the second embodiment raised to the second level via the lifting mechanism.











DETAILED DESCRIPTION OF THE INVENTION




Referring now to the drawings wherein the showings are for purposes of illustrating preferred embodiments of the present invention and not for purposes of limiting the same,

FIG. 1

is a perspective view of a wheelchair


10


in a first embodiment of the present invention. The wheelchair


10


of the first embodiment is comprised of a support frame


12


to which is attached at least two main wheels


14


, a seat base


18


and at least one security beam


26


. The wheelchair


10


shown in

FIG. 1

comprises additional components including a pair of transit wheels


16


, a pair of arm rests


24


, a seat back


20


and a head rest


22


. The seat base


18


is configured for selectively raising or lowering a patient between a first level


54


and a second level


56


. Such selective raising and lowering may be accomplished through a lifting mechanism


32


, as can be seen in FIG.


2


and in

FIGS. 10 and 11

.




Advantageously, as will be discussed in greater detail below, the combination of the movable seat base


18


with the at least one security beam


26


allows a patient to transfer from an article of furniture to the wheelchair


10


utilizing the force of gravity so that the patient is simultaneously moving downward and laterally while holding on to the security beam


26


during the transfer to the wheelchair


10


of the first embodiment. For example, during a transfer of the patient from a bed to the wheelchair


10


, the seat base


18


is moved to the first level


54


that is at a lower level than that of the bed so that the patient is transferred to the seat base


18


in a downward motion. The patient may hold onto the security beam


26


which extends outwardly from the wheelchair


10


so that the patient may steady themselves during the transfer.




Alternately, the patient may transfer from the wheelchair


10


to a living room chair wherein the seat base


18


is moved to the second level


56


that is at a higher level than that of the living room chair. Again, gravity is utilized such that the patient is moving downward into the living room chair while the patient holds onto the security beam


26


during the transfer for additional stability. Only the application of a lateral force need be provided to perform each transfer. The lateral force may be applied solely by the patient or with assistance, such as by a caregiver. A flexible plastic sheet may be extended between the wheelchair


10


and the article of furniture so that the patient may slide across the gap therebetween. Additionally, the wheelchair


10


of the present invention may comprise a pair of anti-tip booms


28


to prevent tipping during use of the security beams


26


in patient transfers, as will be discussed in greater detail below.




Referring now more particularly to

FIGS. 1 and 2

, the wheelchair


10


of the first embodiment may include the pair of transit wheels


16


although a single transit wheel


16


may be provided. Generally smaller in diameter than the main wheels


14


, the transit wheels


16


are typical of conventional wheelchairs and may be mounted to the support frame


12


such that they are free to swivel or caster about an angle perpendicular to the axis of rotation of the transit wheels


16


. Alternatively, the wheelchair


10


may include relatively small diameter main wheels


14


as can be seen in

FIGS. 10 and 11

such that the turning radius of the wheelchair


10


is relatively tight. Such a tight turning radius may allow a caregiver to maneuver the wheelchair


10


around obstacles and through doorways such as may exist in confined spaces of a home.




Referring back now to

FIGS. 1 and 2

, the transit wheels


16


may be mounted on the support frame


12


aft of the main wheels


14


. Alternately, the transit wheels


16


may be mounted forward of the main wheels


14


, as is the case for conventional wheelchairs. The transit wheels


16


provide lateral and forward/aft stability to the wheelchair


10


during normal operation thereof. The transit wheels


16


may also provide steering or directional control to the wheelchair


10


. The anti-tip booms


28


provide lateral and forward/aft stability to the wheelchair


10


when the patient is being transferred into or out of the wheelchair


10


, as will be discussed in greater detail below. It should be noted that the distance in the direction of travel from the main wheels


14


to respective ends of the anti-tip booms


28


is fairly long as compared to the relatively short distance from the main wheels


14


to the transit wheels


16


.




Turning now to

FIG. 3

, shown is a plan view of the wheelchair


10


of the first embodiment taken along line


3





3


of

FIG. 2

illustrating the seat base


18


disposed between the main wheels


14


. The support frame


12


has a front, a rear


44


, and opposing sides


46


with the front facing in a forward direction


48


and the rear


44


facing in an aft direction


50


. The opposing sides


46


of the support frame


12


face in opposing lateral directions


52


. The main wheels


14


are mounted on the support frame


12


and may be mounted on either side


46


of the support frame


12


as shown in FIG.


1


. The main wheels


14


may be mounted coaxially although the main wheels


14


may be staggered wherein one of the main wheels


14


is disposed forward of the other one of the main wheels. It contemplated that there are many other configurations for mounting the main wheels


14


. For example, a main wheel


14


may be mounted inboard of a respective side


46


of the support frame


12


such that the support frame


12


extends laterally past the main wheel


14


.




Furthermore, it is contemplated that the wheelchair


10


may be configured such that a single main wheel


14


is combined with a pair of transit wheels


16


in a tricycle arrangement. In such a configuration, the single main wheel


14


may be generally disposed in front of the seat base


18


and generally in the center of the support frame


12


between the opposing sides


46


. Patient transfer may also be enhanced by providing relatively small diameter main wheels


14


that have an overall height that is significantly less than the normal height of the seat base


18


. The main wheels


14


may be of pneumatic construction in order to provide shock absorbing characteristics, quiet operation, and ease of rolling on rough terrain for the wheelchair


10


.




The support frame


12


may be fabricated of tubing that is interconnected via any number of well-known means such as welding, with mechanical fasteners or by other means. The tubing may have a circular cross-section but may be configured with any number of cross-sectional geometries. Optionally, the support frame


12


may be fabricated of plate stock or it may be of monocoque construction. The support frame


12


may be of metallic construction such as aluminum or steel. However, any number of materials may be utilized for forming the support frame


12


such as graphite/epoxy, fiberglass, or polymeric material such as polyethylene.




Turning now to

FIGS. 2 and 3

, as can be seen, the seat base


18


is disposed upon the support frame


12


between the main wheels


14


. The seat base


18


may be positioned such that a majority of the patient's weight is directed or biased over the main wheels


14


, as can be seen if

FIGS. 10 and 11

. However, in the configuration described above wherein a respective main wheel


14


may be mounted between a side


46


and the midpoint of the support frame


12


, each side


46


of the seat base


18


may extend along the width of the support frame


12


so that each side


46


of the seat base


18


extends past the main wheel


14


.




As was mentioned above, the seat base


18


may be configured for selectively raising and lowering a patient between the first level


54


and the second level


56


.

FIG. 2

is a side elevational view of the wheelchair


10


of the first embodiment illustrating the seat base


18


raised to the second level


56


. As can be seen, the wheelchair


10


includes a lifting mechanism


32


configured for selectively raising and lowering the seat base


18


. The lifting mechanism


32


may comprise a scissors jack having linkages with the horizontal diagonals thereof being alternately lengthened and shortened by a horizontally-driven crank


58


in order to selectively raise and lower the seat base


18


, as can be seen if

FIGS. 10 and 11

.




Optionally, the lifting mechanism


32


may comprise a pneumatic or hydraulic jack wherein compressed air or hydraulic fluid, respectively, may be alternately driven into and exhausted out of an actuator cylinder interposed between the support frame


12


and the seat base


18


in order to raise and lower the seat base


18


. However, it will be recognized that the lifting mechanism


32


may be comprised of a number of alternative devices, any of which may be utilized for selectively raising and lowering the seat base


18


. The lifting mechanism


32


may be configured for lowering the seat base


18


to the first level


54


such that the patient may be lifted off of the floor with the aid of the security beams


26


. In such a scenario, it is contemplated that the security beams


26


may be horizontally oriented and slipped under the armpits of the patient. In this regard, the wheelchair


10


acts as a jack to lift the patient up to a height sufficient for transfer into the wheelchair


10


or into an adjacent article of furniture.




Turning briefly now to

FIG. 5

, shown is a side elevational view of the seat base


18


illustrating a sliding mechanism for translating the seat base


18


in the lateral direction


52


. The seat base


18


may be configured to be relatively wide such that the seat base


18


extends over the wheels when the seat base


18


is moved laterally. Such a wide seat base


18


may help to bridge the gap between articles of furniture and the like. In this regard, the relatively wide seat base


18


may simplify patient transfers.




The seat base


18


may be configured to be selectively translatable in the lateral direction


52


wherein the seat base


18


may be slidably mounted upon the support frame


12


. In a preferred embodiment, the seat base


18


is configured to translate six inches in a lateral direction


52


from a neutral or central position. Additionally, the seat base


18


may also be configured to translate six inches in an opposite lateral direction


52


. However, it will be recognized that the seat base


18


may be configured to translate over any distance in either of the opposing lateral directions


52


.




A locking feature may be incorporated into the wheelchair


10


of the first embodiment to selectively lock the seat base


18


into a neutral or centered position. The locking mechanism may also be utilized to lock the seat base


18


into either one of the lateral positions, including any intermediate position, in order to restrict lateral movement of the seat base


18


during a transfer operation. Also, the seat base


18


may be configured to be pivotable about a vertical axis to aid in the transfer of the patient into and out of the wheelchair


10


. The pivot point may be located generally near a center position of the seat base


18


. However, the seat base


18


may be configured to be pivotable about any point on the wheelchair


10


, such as near a corner of the seat base


18


perimeter.




Referring back to

FIG. 1

, shown is the pair of security beams


26


having substantially horizontal orientations and projecting outwardly in the forward direction


48


although it is contemplated that only the single security beam


26


may be provided with the wheelchair


10


. As can be seen, a security beam


26


is disposed adjacent each of the main wheels


14


. The security beams


26


may have a substantially vertical orientation. As was earlier mentioned, the security beams


26


are configured as hand holds for the patient when transferring onto and off of the seat base


18


. In this regard, it is contemplated that the security beams


26


may be configured as an elongate member of cylindrical cross-section, at least in the area where the patient may hold onto the security beam


26


. In consideration of the desire to provide a hand hold that may be easily grasped by the human hand, a diameter of one to one and one-half inches may be a preferred size for the security beam


26


.




A preferred length of the security beams


26


may be forty inches in order to provide a length sufficiently extending past the wheelchair


10


such that a patient sitting on an adjacent article of furniture may easily grasp the security beam


26


prior to transferring into the wheelchair


10


. However, it is contemplated that there are many shapes, sizes and configurations for the security beam


26


that may be workable. Shown in

FIGS. 1 and 2

as being disposed adjacent the arm rests


24


, the security beams


26


may be connected thereto by any conventional means such as with fittings and mechanical fasteners.




The security beams


26


may also be connected to the support frame


12


via vertical members that place the security beam


26


at approximately the same height as the arm rests


24


. Furthermore, the security beam


26


may be configured to be selectively raised and lowered either independently, or in conjunction with the seat base


18


, as an additional feature which may increase the flexibility of the manner in which the patient transfer may be performed. The security beams


26


may be attached to arm rests


24


that may be included with the wheelchair


10


of the first embodiment. In addition, the security beams


26


may be attached to a security beam socket


86


disposed on a back side of the seat back


20


. The security beam socket


86


may be seen in

FIGS. 12

,


16


and


17


.




The security beams


26


may be configured to be axially extendable such that the overall length of the security beams


26


may be extended beyond an initial length. In this regard, the security beams


26


may be comprised of slidable, coaxial sleeves configured to telescope outwardly. The sleeves may be manually extended outwardly to a desired length. A locking collar may be provided at the end of each sleeve to lock the individual sleeves in position once the security beam


26


is extended to the desired position. The security beam


26


may be configured to be pivotable between the substantially vertical orientation and the substantially horizontal orientation and may be completely detachable from the wheelchair


10


. The security beams


26


may be locked in either of the orientations by means of locking pins.




Additionally, it is contemplated that the security beams


26


may be pivoted and locked into any position intermediate the substantially vertical orientation and the substantially horizontal orientation such as by means of a spring-loaded, notched fitting located at the pivot joint. In the horizontal orientation, the security beam


26


may be fitted with fittings that mate with sockets disposed, for example, on a bathroom wall near a toilet or a shower. The security beams


26


may be placed in the mating sockets to provide temporary banisters or railings to support the patient as they transfer from the wheelchair


10


to the toilet or shower. The security beams


26


may also be configured to be removable in order to increase the compactness and reduce the weight of the wheelchair


10


to enhance its storability and to make it more convenient to transport, such as in an automobile or van.




Turning now to

FIG. 6

, shown is the wheelchair


10


of the first embodiment comprising the seat back


20


and the head rest


22


. The seat back


20


may be reclinable and pivotable between generally upright and reclined positions about an aft end of the seat base


18


. In the upright position, the seat back


20


may be disposed in an orientation similar to that of the seat back


20


of a living room chair. In the reclined position, the seat back


20


may be disposed in a substantially horizontal orientation wherein the seat back


20


is substantially parallel with the seat base


18


such that the occupant is lying flat. Furthermore, the seat back


20


may be pivoted and locked into any position intermediate the generally upright and reclined positions. For example, the seat back


20


may be reclined to a position approximately midway between the upright and reclined positions so that the patient's hair may be washed in a hair washing basin at a hair salon. The head rest


22


, normally disposed above the seat back


20


, may be configured to be detachable from the seat back


20


such that it may be removed to avoid interference with the washing basin.




Referring to

FIG. 4

, shown is a plan view of the wheelchair


10


illustrating the pair of arm rests


24


projecting in the lateral direction


52


. As was mentioned above, the arm rests


24


may be configured to be horizontally pivotable. A respective one of the arms rests


24


may be disposed above each side


46


of the seat base


18


. A clevis and pin arrangement may be included between a respective one of the arm rests


24


and the seat back


20


at the intersection thereof to provide the pivoting feature of the arm rests


24


. In the scenario described above wherein the head rest


22


may be temporarily removed from the reclined seat back


20


to facilitate washing of the patient's hair in a washing basin, the arm rest


24


may also be temporarily pivoted out of the way or altogether removed from the seat back


20


to further facilitate such an activity. It is contemplated that the seat back


20


itself may be removable to reduce the overall height of the wheelchair


10


in order to make it more convenient to transport. In this regard, the seat base


18


itself may further be configured to be removable from the wheelchair


10


in order to provide an additional measure of compactness.




Referring briefly now to

FIGS. 2 and 3

, shown is a plan view of the wheelchair


10


of the first embodiment illustrating the anti-tip booms


28


being substantially horizontally disposed and projecting in the forward direction


48


adjacent the main wheels


14


. As was mentioned earlier, the anti-tip booms


28


, when extended in the forward direction


48


, provide stability for the wheelchair


10


in the forward direction


48


against tipping such as when the patient places their weight upon the security beam. Such additional stability may be required beyond that which is provided by the combination of the main wheels


14


with the transit wheels


16


. The anti-tip booms


28


may be configured to react any downward force that is placed thereupon by the patient. In order to provide additional stability for the wheelchair


10


in the lateral direction


52


, a respective one of the anti-tip booms


28


may be configured to project in one of the opposing lateral directions


52


. Such an orientation of the anti-tip booms


28


may be desirable when the patient is transferring into and out of the side


46


of the wheelchair


10


.




The lateral orientation of the anti-tip booms


28


may further be desirable when the seat base


18


is translated laterally or pivoted and the arm rests


24


are also pivoted or removed for simplifying the transfer of the patient into and out of the side


46


of the wheelchair


10


. The anti-tip booms


28


may be configured to be pivotable and locked into any position that is intermediate the forward-projecting orientation and the laterally-projecting orientation. Similar to the above-described telescoping arrangement of the security beams


26


, the anti-tip booms


28


may be likewise comprised of telescoping, coaxial sleeves that may be manually extended to a desired length and locked into place via pins or a locking collar. The anti-tip booms


28


may include caster wheels


30


, skids, suction cups and the like on the extreme end of each anti-tip boom


28


. However, any number of devices may be incorporated into the respective ends of the anti-tip booms


28


. The anti-tip booms


28


may be configured such that the caster wheels


30


, skids, or alternative devices mounted on the end of the anti-tip booms


28


are fixed a few inches above the floor when the anti-tip booms


28


are retracted, but are placed in contacting relation with the floor once the anti-tip booms


28


are extended.




Referring now to

FIG. 7

, shown is a perspective view of the wheelchair


10


further comprising a winch motor


34


and a winch pulley


36


mounted on the vertically-disposed security beam


26


. A winch cable


38


may be connected to the patient via a shoulder harness or a body harness


40


. Rotation of the winch motor


34


causes the winch cable


38


to alternately raise and lower the patient. The winch pulley


36


, although shown as being disposed on an end of the security beam, may be configured to be removable therefrom. Also, the winch pulley


36


may be disposed anywhere along a length of the security beam


26


although shown in

FIG. 7

as being disposed on an end thereof.




The shoulder or body harness


40


may be padded in order to provide cushioning to the patient. The patient may be raised or lowered by operating the winch motor


34


to alternately retract or extend the winch cable


38


. It is contemplated that the winch motor


34


may be utilized to raise the patient, such as from a supine position on a bed, to a sitting position, prior to initiation of the transfer of the patient from the bed to the wheelchair


10


. It is contemplated that the winch motor


34


may be electrically powered such as by a battery, which may be disposed on the support frame


12


under the seat base


18


.




In this regard, it is further contemplated that the wheelchair


10


of the first embodiment may further comprise a motor mounted on the support frame


12


. The motor may be configured for driving the main wheels


14


in order to propel the wheelchair


10


. Additionally, the motor may be configured for raising and lowering the seat base


18


. Other features that may be powered by the motor include the reclining of the seat back


20


, pivoting of the arm rests


24


and anti-tip booms


28


, and axial extension of the anti-tip booms


28


. The pivoting and the axial extension of the security beams


26


may also be actuated by the motor wherein the power may be provided by the battery which may be mounted adjacent the motor on the support frame


12


so as to maintain a low center of gravity. Additionally, the seat base


18


, seat back


20


, arm rests


24


and head rest


22


may be combined into a single powered seating unit similar to powered seats utilized in many automobiles.




Referring now to

FIGS. 10 and 11

, shown is the wheelchair


10


with main wheels


14


that are of a smaller diameter than that illustrated in

FIGS. 1 through 8

. As was mentioned above, the smaller diameter main wheels


14


provide a tighter turning radius to allow a caregiver to more easily maneuver the wheelchair


10


around obstacles and through doorways in the confined spaces of a home. Patient transfers may also be enhanced by providing relatively small diameter wheels that have an overall height that is significantly less than the normal height of the seat base


18


such that the seat base


18


may be laterally extended over the wheels in order to minimize the gap between the wheelchair


10


and the article to which the patient is to be transferred. By configuring the wheelchair


10


with a relatively wide seat base


18


, the seat base


18


may be moved closer to the article of furniture, thus reducing the gap therebetween. A flexible plastic sheet may be utilized to assist the caregiver in transferring the patient across the gap such that the patient will not accidentally fall between the gap, as will be discussed in more detail below.




In

FIG. 10

, the wheelchair


10


of the first embodiment is shown with the seat base


18


being lowered to the first level


54


. In

FIG. 11

, the seat base


18


is shown being raised to the second level


56


. The lifting mechanism


32


illustrated in

FIGS. 10 and 11

is a scissors jack configuration operated by the crank


58


in the manner previously described for the first embodiment. The arm rests


24


and the seat back


20


are configured to move upwardly and downwardly with the seat base


18


so as to allow the patient to steady themselves with the arm rests


24


and security booms during transfers. As can also be seen in

FIGS. 10 and 11

, the anti-tip booms


28


may be extended to prevent the wheelchair


10


from tipping over when the weight of the patient is extended over the main wheels


14


. Caster wheels


30


may be provided on ends of the anti-tip booms


28


to allow the wheelchair


10


to be maneuvered during transfer operations.




A footrest


60


or a pair of footrests


60


may be included in the wheelchair


10


of the first embodiment. One configuration of the footrest


60


may be seen in

FIGS. 10 and 11

disposed forward of the scissors jack near the anti-tip booms


28


. The footrest


60


may be configured such that the patient may stand on the footrest


60


with the anti-tip booms


28


extended during transfers. The footrest


60


may also be provided in the wheelchair


10


configurations shown in

FIGS. 1 through 8

. It is contemplated that the wheelchair


10


of the first embodiment shown in

FIGS. 10 and 11

may also be provided in an electric version wherein the motor for propelling the wheelchair


10


may be mounted under the seat base


18


adjacent batteries in a manner similar to that described above for the wheelchair


10


configurations of

FIGS. 1 through 8

. The security beams


26


may also be provided in the wheelchair


10


of

FIGS. 10 and 11

.




The operation of the wheelchair


10


of the first embodiment will now be discussed. Although operable in the conventional manner when transporting a seated occupant, the wheelchair


10


advantageously includes the additional combined features of the selectively moveable seat base


18


with the at least one security beam


26


for transferring the patient into and out of the seat base


18


. Importantly, as was mentioned earlier, the present invention allows the patient to transfer from an article of furniture to the wheelchair


10


, utilizing the force of gravity so that the patient is moving simultaneously downward and laterally while holding onto the security beam


26


during the transfer to the wheelchair


10


. For example, during a transfer of the patient from a bed to the wheelchair


10


, the wheelchair


10


is moved adjacent the bed and positioned thereagainst in side-by-side arrangement.




If so equipped, brakes for the main wheels


14


may be engaged to restrict movement thereof. If included, the arm rest


24


nearest the bed may be pivoted from its normal forward facing direction to a lateral direction


52


so that it does not block lateral movement of the patient. The security beam


26


may then be attached to the wheelchair


10


and moved to a vertical orientation. If permanently affixed to the wheelchair


10


, the security beam


26


may be axially extended in order that the patient may conveniently grasp the security beam


26


prior to the transfer. Optionally, the security beam


26


may be installed in the horizontal orientation and may be axially extended so that it rests on the bed.




The patient can then use the security beam


26


as a portable banister or hand rail to enable use of the patient's hand, arm and upper-torso muscles to aid in the transfer. If a pair of security beams


26


is provided, the pair of security beams


26


may be placed parallel to each other on the bed straddling the seated patient. Such an arrangement may enable the patient to walk their hands along the security beams


26


during a transfer. The anti-tip booms


28


may be extended to any length and may be pivoted into the forward facing or lateral directions


52


as required in order to provide stability against tipping of the wheelchair


10


as may otherwise occur during application of the patient's weight upon the security beam


26


.




The anti-tip booms


28


act as a brace to prevent the wheelchair


10


from tipping over when weight is placed on the security beams


26


ahead of the chair or to the wheelchair


10


side


46


. The seat base


18


may be laterally translated over the main wheels


14


nearer to the bed to decrease the distance over which the patient must be transferred. A flexible plastic sheet may be utilized as a transfer aid to slide the patient across the gap between the wheelchair


10


and the bed. The flexible plastic sheet may also span any differential in height between the wheelchair


10


and the bed. Preferably, the wheelchair


10


may be raised to the second level


56


such that the seat base


18


is higher than the bed. By using a flexible plastic sheet, the patient may then be slid slightly downwardly across the gap on the flexible plastic sheet from the seat base


18


to the bed.




Additionally, if so configured, the seat base


18


may be pivoted to simplify the transfer. The seat base


18


is moved to the first level


54


that is at a lower level than that of the bed so that the patient is transferred from the bed down to the seat base


18


. In this regard, a motorized bed that may be raised above the level of the seat base


18


may be advantageously utilized. Furthermore, the motorized bed may be utilized to raise the patient from a prone or supine position, where the patient is laying horizontally on the bed, up to a more upright sitting position. If the patient is unable to move from a supine position to a sitting position, either acting alone or with assistance, the combination of the winch motor


34


, winch pulley


36


, winch cable


38


and body harness


40


may be employed to lift the patient. The winch motor


34


may be engaged in order to retract the winch cable


38


and thereby raise the patient to a sitting position.




Once in the sitting position, the patient may grab one or both of the security beams


26


to maintain balance and stability during the transfer. If capable, the patient may stand, utilizing the security bars for support. The patient is then laterally moved toward the seat base


18


while the force of gravity acts to simultaneously pull the patient down toward the seat base


18


. Here again, the flexible plastic sheet may be utilized to allow the patient to slide across the gap between the wheelchair


10


and the bed. If unable to move laterally under their own power, the patient may be assisted. Once the patient is positioned upon the seat base


18


, the body harness


40


may be removed and the winch cable


38


stowed. The anti-tip booms


28


and security beams


26


may be retracted and the arm rest


24


returned to their normal positions. The patient can then be wheeled about in the wheelchair


10


under their own power or with the assistance of a caregiver.




Transfer of the patient out of the wheelchair


10


and into an article of furniture, such as a living room chair, is accomplished in the reverse order as that described above. A typical sequence of operations when transferring a patient out of the wheelchair


10


may start with positioning the wheelchair


10


adjacent the article to which the patient is to be transferred. The main wheels


14


may be locked to prevent movement of the wheelchair


10


. The security beams


26


and anti-tip booms


28


may then be oriented in a forward direction


48


, laterally or in any intermediate orientation.




If so configured, the anti-tip boom


28


may then be extended to the desired length and locked into place. The seat base


18


is raised above the level of the article to which the patient is transferred. Arm rests


24


may be pivoted out of the way or removed. The winch motor


34


may be utilized to assist the patient in rising to a standing position if the patient is incapable of supporting their own weight. The patient is then laterally moved to the article of furniture utilizing the force of gravity to assist in the transfer. After the transfer, the anti-tip booms


28


and security beams


26


may be retracted and the body harness


40


removed.




During the transfer, the patient may grasp the security beam


26


which extends outwardly from the wheelchair


10


so that the patient may steady themselves and maintain their balance. Alternately, the patient may transfer from the wheelchair


10


to a living room chair wherein the seat base


18


is moved to the second level


56


that is at a higher level than that of the article of furniture. Again, gravity is utilized such that the patient is moving downward into the living room chair while the patient holds onto the security beam


26


during the transfer for additional stability. Only the application of a lateral force need be provided to perform each transfer. The lateral force may be applied solely by the patient or with assistance, such as by a caregiver.




As was earlier mentioned, the security beams


26


may also be utilized in raising the patient up off of the floor by slipping the security beams


26


underneath the armpits of the patient. Furthermore, it is contemplated that the wheelchair


10


of the present invention may be utilized to perform patient transfer between many other articles including a shower and an automobile seat.




Referring now to

FIGS. 12-17

, the wheelchair


10


may also be provided in a second embodiment wherein a stretcher topping


62


may be disposed on a storage compartment


64


which is slidably mounted on the support frame


12


. Advantageously, the combination storage compartment


64


and stretcher topping


62


of the second embodiment and the seat base


16


of the first embodiment are each configured such that they may be interchanged with each other. In this manner, the user is provided with two options for supporting the patient.




The stretcher topping


62


of the second embodiment is comprised of the storage compartment


64


, a seat base assembly


66


, a reclinable seat back


20


and a leg support


78


, as is shown in FIG.


12


. The seat base assembly


66


includes potty capabilities for the patient due to the inclusion of a potty panel


70


disposed underneath a part of the seat panel


68


. Advantageously, the stretcher topping


62


may be arranged in a planar, stretcher-like configuration as shown in

FIG. 12

by horizontally aligning the seat back


20


and the leg support


78


with the seat base assembly


66


. In the stretcher-like configuration, the stretcher topping


62


allows the patient to lie in a supine or prone position.




The seat base assembly


66


is mounted upon the storage compartment


64


, which in turn is mounted on the support frame


12


in such a manner that the patient's weight may be supported without propping up either one of the leg support


78


or the seat back


20


thereof. However, a push handle


84


may be provided under the seat back


20


if so desired in order to provide additional support for the seat back


20


when additional weight is placed thereupon such as may occur when the patient is using the potty panel


70


, as will be described in greater detail below.




In addition, the stretcher topping


62


may be arranged in a seated configuration wherein the seat back


20


is positioned into a reclined orientation with the leg support


78


extending downwardly in an angled orientation from the seat base assembly


66


. The leg support


78


may be removed to enable lateral sliding of the stretcher topping


62


without the leg support


78


interfering with the main wheels


14


. As will be appreciated, the stretcher topping


62


may be arranged in an infinite number of configurations due to the capability of the seat back


20


and the leg support


78


to be positioned in any orientation between and including the substantially horizontal orientation and the vertical orientation. Furthermore, the seat back


20


is configured such that it may be folded on top of the seat base assembly


66


to reduce the size of the stretcher topping


62


. The leg support


78


is configured to be completely removable in order to enhance the storage and transportability of the wheelchair


10


.




Importantly, the storage compartment


64


of the wheelchair


10


of the second embodiment is laterally slidably mounted upon the support frame


12


with the seat base assembly


66


being mounted upon the storage compartment


64


. By configuring the storage compartment


64


to be laterally slidable in combination with its height adjustability between first and second levels


54


,


56


, the stretcher topping


62


may be positioned in any position relative to an article to or from which the patient may be transferred. More specifically, the wheelchair


10


is configured such that the stretcher topping


62


may be raised or lowered until it is positioned at a level that is slightly lower or higher than that of an article, such as a bed, to which or from which the patient may be transferred. The stretcher topping


62


is configured such that it may also be laterally slid over one of the main wheels


14


for close placement near the patient.




By positioning the stretcher topping


62


close to the patient, any gap that may otherwise exist between the stretcher topping


62


and the article may be minimized or altogether eliminated. With the gap eliminated between the stretcher topping


62


and the auricle, the patient may be easily rolled or slid from the bed onto the stretcher topping


62


, as will be explained in greater detail below. Gravity may be used to assist in the transfer of the patient between the stretcher topping


62


and the article. In each case, the stretcher topping


62


may preferably, but optionally, be positioned such that it is lower than the article from which the patient is to be transferred. Conversely, the stretcher topping


62


may be positioned such that it is higher than the article to which the patient is to be transferred.




Referring to

FIG. 12

, shown is a side view of the wheelchair


10


of the second embodiment showing the stretcher topping


62


mounted upon the laterally slidable storage compartment


64


. The wheelchair


10


of the second embodiment shares a commonality with several components of the wheelchair


10


of the first embodiment. In this regard, the wheelchair


10


of the second embodiment is comprised of the support frame


12


having the front


42


, the rear


44


and the opposing sides


46


. The support frame


12


may be configured in a manner as described above for the first embodiment. The front


42


and the rear


44


of the support frame


12


face in respective forward and aft directions


48


,


50


with the opposing sides


46


facing in opposing lateral directions


52


. The support frame


12


may be fabricated from any material or combination of materials as described above in the support frame


12


of the first embodiment.




The two main wheels


14


are mounted on the support frame


12


wherein a respective one of the main wheels


14


is mounted adjacent a respective one of the opposing sides


46


in a manner similar to that shown in FIG.


15


. However, it is contemplated that the main wheels


14


may be provided in any quantity and may be mounted in any number of locations on the support frame


12


, as was also mentioned above in the description of the first embodiment. It should be noted that the main wheels


14


of the second embodiment may be of a smaller size than the main wheels


14


of the first embodiment in order to provide clearance for the stretcher topping


62


so that it may be slid over either one of the main wheels


14


without regard to height setting of the stretcher topping


62


(i.e., whether it is placed at the first level


54


or at the second level


56


).




The pair of transit wheels


16


may be included with the wheelchair


10


and may be mounted on the support frame


12


forward or aft of the main wheels


14


. The transit wheels


16


are configured to add stability to the wheelchair


10


in a manner similar to that shown in

FIGS. 1 and 15

. However, only a single one of the transit wheels


16


may be included or multiple transit wheels


16


may be included with the wheelchair


10


of the second embodiment. In a manner similar to that shown and described above for the first embodiment, the transit wheels


16


may be mounted on the support frame


12


aft of the main wheels


14


. Alternately, the transit wheels


16


may be mounted forward of the main wheels


14


, as is the case for conventional wheelchair


105


. The transit wheels


16


provide lateral and forward/aft stability to the wheelchair


10


during normal operation thereof. The transit wheels


16


may also provide steering or directional control to the wheelchair


10


.




Referring now to

FIGS. 14 and 16

, shown is the laterally sliding storage compartment


64


mounted on the support frame


12


. A pair of sliding mechanisms


82


, shown in


14


, may be interposed between the storage compartment


64


and the support frame


12


. Each one of the sliding mechanisms


82


may preferably, but optionally, consist of a generally U-shaped channel that may be affixed to the support frame


12


. Each one of U-shaped channels may be comprised of a pair of upwardly extending flanges with an upper edge of each flange having a down turned flange, as is shown in FIG.


14


. Each one of the U-shaped channels may be sized and positioned to extend across a width of the support frame


12


. The sliding mechanism


82


may be fabricated from any type of material such as, for example, metal or plastic such as polyethylene plastic.




A complementary set of rollers


88


may be affixed to a front wall as well as to a rear wall of the storage compartment


64


. The rollers


88


may be sized and configured to match an inner geometry of each of the U-shaped channels such that the rollers


88


may be contained within the confines of the channels. Stops may be included on opposing ends of each one of the U-shaped channels in order to prevent the rollers


88


from rolling out of either one of the ends of the U-shaped channel when the storage compartment


64


is laterally moved via the sliding mechanism


82


.




Each one of the rollers


88


may be secured to the front and rear walls of the storage compartment


64


. Alternatively, a T-shaped extrusion may be fastened to each one of the front and rear walls of the storage compartment


64


, as can be seen in FIG.


14


. Each one of the rollers


88


may be attached to opposing ends of each one of the T-shaped extrusions. Although the sliding mechanism


82


is shown and described as comprising the pair of U-shaped channels, sets of rollers


88


, and T-shaped extrusions, it is contemplated that the sliding mechanism


82


may be comprised of a variety of alternate components and may be arranged in any configuration that provides the feature of lateral slidability of the storage compartment


64


and, hence, the stretcher topping


62


.




The storage compartment


64


may be comprised of a bottom panel, a pair of side walls, and the front and rear walls mentioned above. Each one of the side walls and front and rear walls may extend upwardly from the bottom panel to the seat base assembly


66


. Although shown as being generally rectangularly shaped, the storage compartment


64


may be configured in any number of shapes such as a rounded shape. However, the generally rectangular shape is believed to be advantageous in that the storage compartment


64


may generally match a preferred rectangular shape of the seat base assembly


66


.




In this manner, the side walls and front and rear walls of the storage compartment


64


may be readily fastened to the seat base assembly


66


perimeter. As is illustrated in

FIG. 16

, each one of the upwardly extending side walls and each one of the front and rear walls may include a horizontal outwardly extending flange upon which the seat base assembly


66


may be mounted. A frame may be included with the seat base assembly


66


. The frame may extend around the seat base assembly


66


in order to impart stiffness and strength thereto such that the seat base assembly


66


may support the weight of the patient.




The bottom panel, side walls, and front and rear walls of the storage compartment


64


cooperate with an underside of the seat base assembly


66


to define a single volume of the storage compartment


64


. Alternatively, the storage compartment


64


may include a vertically disposed divider panel extending upwardly from the bottom panel, as is shown in FIG.


14


. The divider panel may be configured to divide the storage compartment


64


into a forward section


74


and an aft section


76


. The aft section


76


may include a removable drawer


80


for containing various items. For example, the drawer


80


may provide a place to store the plastic sheet that may be used in transferring the patient between the stretcher topping


62


and the article.




Other items may also be stored in the drawer


80


such as plastic bags for use with the potty panel


70


during patient evacuation, as will be discussed in greater detail below. The drawer


80


may be configured such that it may be slidably advanced into and withdrawn from the aft section


76


similar to the operation of a clothes dresser drawer


80


. A handle or small opening


90


may be included on an outward facing or exposed side of the drawer


80


similar to the opening


90


shown in FIG.


15


. The opening


90


may allow for the easy withdrawal and re-insertion of the drawer


80


into the aft section


76


of the storage compartment


64


.




Referring still to

FIGS. 14 and 16

, the seat base assembly


66


may be comprised of a removable seat panel


68


and a potty panel


70


. The seat panel


68


may preferably be sized and configured such that is stackable upon and removable from a similarly sized one of the potty panels


70


. As can be seen in

FIGS. 14 and 15

, the potty panel


70


has an aperture


72


formed therethrough that opens into the storage compartment


64


. For configurations of the storage compartment


64


that include the divider panel, the aperture


72


may be located such that it opens into the forward section


74


only and does not open into the aft section


76


. The aperture


72


may preferably be approximately centered between sides of the stretcher topping


62


such that the patient may evacuate while being supported by the potty panel


70


without having to move to either side


46


of the seat base assembly


66


. During use of the potty panel


70


, the seat panel


68


is temporarily removed to expose the potty panel


70


. Although configurable in a number of different shapes and sizes, the aperture


72


may preferably have a generally rounded or oval shape and may be sized approximately as shown in

FIGS. 14 and 15

.




An additional feature of the second embodiment relates to the lateral sliding capability of the storage compartment


64


. In order to enhance this feature such that the stretcher topping


62


may be moved close to the patient during transfers, the storage compartment


64


may extend across only a portion of the seat base assembly


66


as compared to configurations wherein the storage compartment


64


extends across an entire width of the seat base assembly


66


. This feature allows the stretcher topping


62


to be laterally moved toward one of the main wheels


14


until a side wall of the storage compartment


64


contacts the main wheel


14


. Such a scenario may occur if the stretcher topping


62


were lowered to the first level


54


. However, if the stretcher topping


62


were raised up to the second level


56


, the bottom panel of the storage compartment


64


may be configured such that it clears the main wheels


14


when laterally extended thereover.




Both the potty panel


70


perimeter and the seat panel


68


perimeter may be shaped and sized to generally match the shape and size of the storage compartment


64


perimeter such that the frame thereof may collectively support the potty panel


70


and the seat panel


68


. The potty panel


70


may be fabricated of plastic material such that it may be easily cleaned after use. The seat panel


68


may also be fabricated of plastic material that may further be covered with a padded cushioning material in order to provide a soft layer upon which the patient may be comfortably supported for an extended period of time. However, it is contemplated that the potty panel


70


and the seat panel


68


may be fabricated from a variety of materials including but not limited to metal, fiberglass, wood, or any combination thereof. Both the seat panel


68


and the potty panel


70


may be removably attached to the storage compartment


64


such that each may be cleaned.




The stretcher topping


62


further includes the seat back


20


which is configured to be reclinable. The seat back


20


is hingedly connected to and pivotable about an aft end of the seat base. The seat back


20


is preferably configured to be positioned at any orientation between and including generally horizontal and vertical orientations. As was earlier mentioned, the seat back


20


may be folded on top of the seat base assembly


66


in order to reduce the size of the wheelchair


10


for storability and transportability purposes.




In addition, the seat back


20


may be extended outwardly in the substantially horizontal orientation as is illustrated in FIG.


12


. Like the seat panel


68


, the seat back


20


may be fabricated from a variety of alternative materials or combinations thereof. Regardless of the particular material from which it is fabricated, it is contemplated that the seat back


20


may be covered with a padded cushioning material to provide a soft, comfortable layer upon which the patient may rest. A relatively thick padded cushion (not shown) may be placed against the seat back


20


to increase patient comfort while sitting in the wheelchair


10


with the patient's legs hanging down. For example, the padded cushion may be sized to be about four inches thick such that the twenty-four inch length of the seat base assembly


66


is reduced to about twenty inches in length to allow the patient to sit upright in a more erect position.




However, during use of the potty panel


70


, the padded cushion may be removed and the patient moved headward to allow the forward part


68




a


of the seat panel


68


to be removed exposing the potty panel


70


, as will be described in greater detail below. Although not shown in the second embodiment, a head rest


22


similar to that described above and shown in

FIGS. 1-9

may be included with the seat back


20


. Arm rests


24


may also be included with the wheelchair


10


. An arm rest


24


may be secured to each of opposing sides


46


of the wheelchair


10


. The arm rest


24


may be configured to be removable in a manner similar to the arm rest


24


of the first embodiment.




The arm rests


24


may be oriented such that they are substantially horizontally disposed above sides


46


of the seat base. The arm rests


24


may further be vertically and/or laterally pivotably attached to the seat back


20


and may each be supported with foldable braces that may be swung up inside of the arm rests


24


such that the arm rests


24


may be folded down flat in alignment with the seat back


20


. In this manner, the patient may be slid on and off of the stretcher topping


62


without encountering obstructions. The arm rests


24


may be configured in a manner similar to that described above for the first embodiment and as shown in

FIGS. 1-4

. At least one security beam


26


may be attached to one of the arm rests


24


as shown in

FIGS. 1-4

. Alternatively, the security beam


26


may be inserted underneath the arm rest


24


wherein a socket is provided for engagement with the security beam


26


.




The push handle


84


may be inserted under the seat back


20


to act as a prop for the seat back


20


. The push handle


84


can be seen in

FIG. 12

as extending upwardly from the rear


44


of the support frame


12


to an underside of the seat back


20


where it may be locked into place while the patient is laying on the stretcher topping


62


. The push handle


84


may be configured to be telescoping such that its height may be reduced during non-use. The telescoping feature of the push handle


84


also allows variable length adjustment thereof such that, depending on whether the stretcher topping


62


is positioned at the first level


54


, the second level


56


or an intermediate level, the push handle


84


may be extended up to the level of the seat back


20


. The telescoping feature of the push handle


84


also allows for adjusting its height to suit a particular user of the push handle


84


.




Referring still to

FIGS. 13-15

, a leg support


78


may be included with the stretcher topping


62


. The leg support


78


may be removably connected to and pivotable about the forward end of the seat base between and including substantially horizontal and vertical orientation, similar to that described above for the seat back


20


. The leg support


78


is shown in the substantially horizontal orientation in

FIGS. 12-13

and in a downwardly angled orientation in

FIGS. 16-17

. The leg support


78


may include pins for mating with complementary sockets in a front


42


of the seat base assembly


66


such that the leg support


78


may be readily removed to reduce the overall size of the stretcher topping


62


. In addition, the leg support


78


may include an outwardly pivotable or foldable foot rest


60


secured thereto as is shown in

FIGS. 15-17

.




The foot rest


60


may be supported by a folding brace disposed on opposing sides


46


of the leg support


78


. Alternatively, the foot rest


60


may be supported by a single brace disposed in an approximate center of the foot rest


60


. The foot rest


60


may preferably be configured such that it may foldable down against the leg support


78


to allow the patient's legs to extend outstretched on the stretcher topping


62


. It is contemplated that the foot rest


60


may be altogether removable from the leg support


78


. During use, the foot rest


60


may be laid flat against the leg support


78


if the patient is lying prone or supine on the stretcher topping


62


. If the patient is to be placed in a seated position, the foot rest


60


may be extended outwardly as shown in

FIGS. 15-17

such that the patient's feet may rest thereupon. Similar to the construction of the seat panel


68


and the seat back


20


, the leg support


78


may be fabricated of any material including wood, metal, plastic or any combination thereof. The leg support


78


may further be covered with a padded cushioning material in order to provide a soft layer to support the weight of the patient.




Collectively, the seat base assembly


66


, the seat back


20


and the leg support


78


may be sized and configured such that the stretcher topping


62


has an overall length and width that will accommodate a wide variety of patients of varying physical proportions. Toward this end, it is contemplated that the stretcher topping


62


may be about sixteen inches in width. The seat base assembly


66


may have a length of about twenty-four inches with the seat panel


68


and the potty panel


70


being of the same dimensions. Alternatively, the potty panel


70


may have a length of about twelve inches while the seat panel


68


may be provided in two parts including an aft part


68




b


and a forward part


68




a


for a combined length of about twenty-four inches for the seat panel


68


.




The forward part


68




a


may be removably secured to the storage compartment


64


above the potty panel


70


while the aft part


68




b


may be either removably or non-removably secured to the storage compartment


64


. The aperture


72


in the potty panel


70


may preferably be oval shaped, as is illustrated in

FIG. 15

, although numerous other shapes are contemplated. Such oval-shaped aperture


72


may preferably have a length of about twelve inches along a major axis and about six inches along a minor axis. A plastic bag such as a trash bag liner may be inserted through the aperture


72


with an upper end of the plastic bag being taped around a perimeter of the aperture


72


prior to evacuation of the patient. After evacuation, the plastic bag may be removed and the seat panel


68


replaced on the potty panel


70


, as will be described in greater detail below.




The divider panel, if included, may be positioned such that the forward section


74


of the storage compartment


64


has a length of about twelve inches and the aft section


76


has a similar length such that the potty panel


70


covers the forward section


74


only, and not the aft section


76


. Of course, the respective lengths of the forward and aft sections


74


,


76


of the storage compartment


64


may vary depending upon the location of the divider panel within the storage compartment


64


and the overall length of the storage compartment


64


. The side walls and the front and rear wall may be sized such that the storage compartment


64


has an overall height of about six inches. The potty panel


70


may preferably be fabricated of plastic such as molded plastic, as was earlier mentioned. The potty panel


70


may have a thickness of about ⅛ of an inch while the seat panel


68


may have a thickness of about ¼ of an inch.




The seat panel


68


may optionally be divided into two parts with one part covering the aft section


76


and being fixed thereupon. The other part of the seat panel


68


may be sized to cover the potty panel


70


such that removal of the forward part


68




a


of the seat panel


68


exposes the potty panel


70


. As was earlier mentioned, the potty panel


70


may be configured such that it is removable for easy cleaning. The forward part


68




a


of the seat panel


68


may also be removable in order to expose the potty panel


70


. Both parts of the seat panel


68


may be sized to have the same thickness and may be fabricated of the same material with padding covering a substantial portion of each of the forward and aft parts


68




a


,


68




b


to increase patient comfort.




The width of the storage compartment


64


may be sized to be equal to that of the seat panel


68


. More preferably however, the storage compartment


64


may be sized such that it spans about ⅓ of a width of the seat base assembly


66


. If the stretcher topping


62


is sized to have a width of about twenty-four inches, the storage compartment


64


may have a width of only eighteen inches such that a six inch wide strip under one of the sides


46


of the seat base assembly


66


is left vacant. This vacant strip allows for the stretcher topping


62


to be laterally moved up to six inches in one direction such that it may be extended over one of the main wheels


14


, as was earlier mentioned. As was earlier mentioned, the leg support


78


may be removed to allow such lateral movement of the stretcher topping


62


. It will be appreciated that a width of the vacant strip may be varied by varying the width and lateral placement of the storage compartment


64


. Such increased width of the vacant strip in turn increases the amount by which the stretcher topping


62


may be laterally extended.




The wheelchair


10


of the second embodiment may further include at least one security beam


26


configured as a hand-hold to aid the patient in transfers to and from the wheelchair


10


, as was described above in the first embodiment. The security beam


26


may be disposed adjacent one of the main wheels


14


in a manner similar to that shown in FIG.


9


. The security beam


26


may also be disposed adjacent the seat base assembly


66


in a manner similar to that shown in

FIGS. 1-4

and as was mentioned above in regards to the first embodiment. In addition, at least one of the security beams


26


may be disposed behind the seat back


20


by plugging into a security beam socket


86


mounted behind the seat back


20


and interposed between the main wheels


14


.




Security beam sockets


86


may also be strategically placed in a number of alternative locations on the wheelchair


10


such as on the support frame


12


so that security poles may be secured thereupon for patient support during transfers and during general use of the wheelchair


10


. Regardless of their location, it is contemplated that each one of the security beams


26


may be configured to be pivotable between substantially vertical and horizontal orientations. Each one of the security beams


26


may also be configured to be extendable outwardly from the wheelchair


10


.




In addition, the anti-tip booms


28


may be included with the wheelchair


10


to prevent tipping when the weight of the patient is concentrated on an end or side


46


of the stretcher topping


62


. Each one of the anti-tip booms


28


may be configured in a manner similar to that described above for the first embodiment and as shown in

FIGS. 1-5

and


9


-


11


. In this regard, the anti-tip booms


28


may be substantially horizontally disposed adjacent one of the main wheels


14


. Furthermore, each one of the anti-tip booms


28


may be configured to axially extendable and project outwardly from the support frame


12


. In addition, each one of the anti-tip booms


28


may be configured to be pivotable between the forward direction


48


and the lateral direction


52


.




As in the first embodiment of the wheelchair


10


having the seat base, the wheelchair


10


of the second embodiment having the stretcher topping


62


may further include a lifting mechanism


32


configured for selectively raising or lowering the storage compartment


64


and, hence, the stretcher topping


62


between the first level


54


and the second level


56


, as shown in FIG.


12


. Such selective raising and lowering may be accomplished through the lifting mechanism


32


which may be configured similar to that shown in

FIGS. 2

,


10


and


11


and as was earlier described in the first embodiment. Such lifting mechanism


32


may be configured as a scissors jack similar to that shown in

FIGS. 10-11

,


12


and


17


and as described above. A gear train reduction (not shown) may be incorporated with the scissors jack in order to reduce the torque required to turn the crank


58


. Alternatively, the lifting mechanism


32


may be configured as a hydraulic jack similar to that shown in FIG.


4


and as was earlier described in the first embodiment.




The operation of the wheelchair


10


of the second embodiment will now be discussed. Although operable in the conventional manner when the stretcher topping


62


is configured for transporting a seated occupant, the wheelchair


10


advantageously includes the additional combined features of the selectively vertically and laterally moveable stretcher topping


62


and storage compartment


64


. Importantly, as was mentioned earlier, the present invention allows the patient to transfer from an article of furniture to the wheelchair


10


, utilizing the force of gravity so that the patient is moving simultaneously downwardly and laterally. If capable, the patient may grasp the security beam


26


, if included, during the transfer to the wheelchair


10


. For example, during a transfer of the patient from a bed to the wheelchair


10


, the stretcher topping


62


of the wheelchair


10


is configured into the seated configuration by adjusting the seat back


20


and leg support


78


to be horizontally aligned with the seat base assembly


66


.




The stretcher topping


62


is laterally moved in conjunction with the storage compartment


64


upon which it is mounted. Once the stretcher topping


62


is moved laterally, the wheelchair


10


may be moved adjacent to the bed and positioned close to the patient in side-by-side arrangement. The height of the stretcher topping


62


may be adjusted so that it is at a lower level than that of the bed. Alternatively, the stretcher topping


62


may be rested upon the bed next to the patient in which case the thickness of the seat base assembly


66


dictates that the bed will necessarily be at a lower level than the stretcher topping


62


. However, a one inch height differential is not believed to hinder lateral translation of the patient from the bed to the stretcher topping


62


. In such instances, the plastic sheet may be placed across an interface between the side


46


of the stretcher topping


62


and the bed so that a slickness of the plastic sheet reduces the force required to laterally move the patient slightly upwardly onto the stretcher topping


62


.




If so equipped, brakes for the main wheels


14


may be engaged to restrict movement thereof. If included, the arm rest


24


nearest the bed may be pivoted from its outwardly facing direction into alignment with the seat back


20


so that it does not block lateral movement of the patient. Likewise, the foot rest


60


, if included, may be folded against the leg support


78


. A security beam


26


may be attached to the wheelchair


10


and moved to a vertical orientation. If permanently affixed to the wheelchair


10


, the security beam


26


may be axially extended in order that the patient may conveniently grasp the security beam


26


during the transfer. The anti-tip booms


28


may be extended to any length and may be pivoted into the forward facing and/or lateral directions


52


as required in order to provide stability against tipping of the wheelchair


10


as may otherwise occur during application of the patient's weight thereupon.




The anti-tip booms


28


act as a brace to prevent the wheelchair


10


from tipping over when weight is placed ahead of the wheelchair


10


or to a side


46


of the wheelchair


10


. As was earlier mentioned, the stretcher topping


62


may be laterally translated over one of the main wheels


14


near the bed to decrease the gap over which the patient must be transferred. A flexible plastic sheet may be utilized as a transfer aid to slide the patient across the gap between the wheelchair


10


and the bed. The flexible plastic sheet may also span any differential in height between the wheelchair


10


and the bed. Preferably, the wheelchair


10


may be raised to a level such that the stretcher topping


62


is lower than the bed. By using a flexible plastic sheet, the patient may then be slid slightly downwardly across the gap on the flexible plastic sheet from the bed to the stretcher topping


62


. A relatively thick, large-sized towel may also be placed on the plastic sheet to reduce the sliding friction when laterally transferring the patient. The towel may also reduce bruising of the patient.




In order to use the potty panel


70


, the stretcher topping


62


is moved into the seated position with the seat back


20


placed in a generally reclined position. The padded cushion, if included, is removed from the seat back


20


and the patient is slid toward the rear


44


of the wheelchair


10


so that the forward part


68




a


of the seat panel


68


may be removed to expose the potty panel


70


. A plastic bag is inserted into the aperture


72


with the upper end thereof being spread out and folded over. The plastic bag may be taped down flat to the potty panel


70


. The patient is then moved over the aperture


72


. Once evacuation of the patient is finished, the patient is moved headward again to allow removal of the plastic bag, the forward part


68




a


of the seat panel


68


is replaced over the potty panel


70


and the patient is then slid forward and placed into a sitting position. The padded cushion may then be replaced and the legs are placed against the leg support


78


and foot rest


60


, if included.




The wheelchair


10


of the second embodiment may be motorized similar to the motorized version of the wheelchair


10


of the first embodiment described above. The lifting mechanism


32


of the second embodiment may be motorized in order to allow vertical height adjustment between the first and second levels


54


,


56


. Furthermore, the stretcher topping


62


may be motorized to pivot the seat back


20


and leg support


78


into the respective orientations whereupon the patient may be moved from a prone or supine position, (i.e., the patient is laying horizontally), up to a more upright sitting position. Power for the motorized version of the first and second embodiments may be supplied by batteries. In the sitting position, the patient can then be wheeled about in the wheelchair


10


under the power of the motor, under their own power, or with the assistance of a caregiver. Transfer of the patient out of the wheelchair


10


and into an article of furniture, such as a living room chair, is accomplished in the reverse order as that described above.




Additional modifications and improvements of the present invention may also be apparent to those of ordinary skill in the art. Thus, the particular combination of parts described and illustrated herein is intended to represent only certain embodiments of the present invention, and is not intended to serve as limitations of alternative devices within the spirit and scope of the invention.



Claims
  • 1. A wheelchair for transporting a patient, comprising:a support frame having a front, a rear, and opposing sides, the front and rear facing in respective forward and aft directions, the opposing sides facing in opposing lateral directions; at least two main wheels mounted on the support frame; a stretcher topping disposed upon the support frame and configured for selectively raising and lowering the patient between a first level and a second level, the stretcher topping including: a storage compartment laterally slidably mounted upon the support frame; a seat base assembly mounted upon the storage compartment and including a removable seat panel stackable upon a potty panel, the potty panel having an aperture formed therethrough and opening into the storage compartment; a reclinable seat back hingedly connected and pivotable about an aft end of the seat base assembly between generally horizontal and vertical orientations; and a leg support removably connected to and configured to be pivotable about the forward end of the seat base assembly between generally horizontal and vertical orientations.
  • 2. The wheelchair of claim 1 further including at least one security beam disposed adjacent one of the main wheels wherein the security beam is configured as a hand hold for the patient when transferring onto and off of the seat base assembly.
  • 3. The wheelchair or claim 1 wherein the security beam is disposed behind the seat back between the main wheels.
  • 4. The wheelchair of claim 1 wherein the storage compartment extends across only a portion of the seat base assembly width such that lateral sliding movement of the storage compartment allows for laterally extending a portion of the stretcher topping side beyond one of the main wheels.
  • 5. The wheelchair of claim 1 wherein the storage compartment is dividable into forward and aft sections.
  • 6. The wheelchair of claim 5 wherein the potty panel opens into the forward section.
  • 7. The wheelchair of claim 5 wherein the aft section of the storage compartment includes a removable drawer slidably insertable thereinto.
  • 8. The wheelchair of claim 1 wherein the leg support is detachable from the seat base assembly.
  • 9. The wheelchair of claim 1 wherein the leg support includes an outwardly pivotable footrest secured thereto.
  • 10. The wheelchair of claim 2 wherein the security beam is pivotable between substantially horizontal and vertical orientations and projects outwardly from the wheelchair.
  • 11. The wheelchair of claim 10 wherein the security beam is configured to be axially extendable.
  • 12. The wheelchair of claim 1 further comprising at least one transit wheel mounted on the support frame forward of the main wheels.
  • 13. The wheelchair of claim 12 wherein the transit wheel is mounted aft of the main wheels.
  • 14. The wheelchair of claim 1 further comprising a lifting mechanism configured for selectively raising and lowering the storage compartment and stretcher topping.
  • 15. The wheelchair of claim 14 wherein the lifting mechanism comprises a scissors jack.
  • 16. The wheelchair of claim 14 wherein the lifting mechanism comprises a hydraulic jack.
  • 17. The wheelchair of claim 1 further comprising a pair of arm rests, each one of the arm rests being substantially horizontally disposed above a side of the seat base assembly.
  • 18. The wheelchair of claim 17 wherein each one of the arm rests is configured to be laterally pivotable.
  • 19. The wheelchair of claim 17 wherein each one of the arm rests is configured to be foldable into alignment with the seat back.
  • 20. The wheelchair of claim 1 further comprising a pair of anti-tip booms, each one of the anti-tip booms being substantially horizontally disposed adjacent a main wheel and projecting outwardly from the support frame.
  • 21. The wheelchair of claim 20 wherein each one of the anti-tip booms is axially extendable.
  • 22. The wheelchair of claim 20 wherein each one of the anti-tip booms is configured such that it may be laterally pivoted between the forward direction and the lateral direction.
CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of U.S. application Ser. No. 10/424,328 filed Apr. 28, 2003, the entire contents of which are incorporated by reference herein.

US Referenced Citations (16)
Number Name Date Kind
3038174 Donovan et al. Jun 1962 A
4856123 Henderson et al. Aug 1989 A
4893827 Gay et al. Jan 1990 A
4920587 Kerr May 1990 A
5134737 Wyman Aug 1992 A
5186585 Sousa Feb 1993 A
5319813 DiMatteo et al. Jun 1994 A
5398357 Foster Mar 1995 A
5454126 Foster et al. Oct 1995 A
5513406 Foster et al. May 1996 A
6089593 Hanson Jul 2000 A
6154899 Brooke et al. Dec 2000 A
6315319 Hanson Nov 2001 B1
D473826 Schlangen Apr 2003 S
6561524 Medina May 2003 B1
6725474 Foster et al. Apr 2004 B2
Continuation in Parts (1)
Number Date Country
Parent 10/424328 Apr 2003 US
Child 10/729203 US