Powered wheelchair having an articulating beam and related methods of use

1. A wheelchair comprising:

a frame including a seat post;

a pair of opposing drive wheels;

a pair of pivoting assemblies, each one of the pivoting assemblies including a drive assembly and a front arm assembly, each one of the pivoting assemblies being associated with one of the drive wheels and pivotally connected to the frame;

each drive assembly including a motor and gearbox that are transversely mounted relative to the frame and operatively coupled to one of the drive wheels;

a battery compartment formed on the frame and located rearward of the drive assemblies;

batteries located in the battery compartment; and

an articulating beam assembly including a transverse member, pair of legs, and a pair of rear wheel assemblies, the legs extending generally rearwardly from opposing ends of the transverse member to the rear wheel assemblies, the transverse member being pivotally coupled to the seat post forward of the batteries;

whereby the battery compartment may be accessed from the rear of the wheelchair between the legs.

2. The wheelchair of claim 1 wherein the transverse member is generally parallel to the axis of rotation of the drive wheels.

3. The wheelchair of claim 1 wherein the articulating beam pivots about a substantially horizontal axis that is approximately perpendicular to the drive wheel axis of rotation.

4. The wheelchair of claim 1 wherein each one of the pivoting assemblies includes a front wheel that is an anti-tip wheel.

5. The wheelchair of claim 4 wherein the anti-tip wheel is suspended from a ground surface on which the wheelchair travels, the wheelchair further comprising a suspension capable of acting on the arm.

6. The wheelchair of claim 1 wherein the front wheel is a castor wheel that is normally in contact with the ground surface on which the wheelchair travels.

7. The wheelchair of claim 1 wherein a centerline of a pivot axis of the pivotal connection between the drive assembly and the frame has a vertical height that is approximately the same or less than the vertical height of an axis of rotation of the front wheel.

8. The wheelchair of claim 7 wherein the motor has a longitudinal axis that is transverse relative to the frame.

9. The wheelchair of claim 7 wherein the drive assembly includes a mount to which the gearbox is affixed, the mount including a surface to which the front arm is rigidly affixed.

10. The wheelchair of claim 9 wherein the mounting is a vertical plate.

11. The wheelchair of claim 1 wherein the gearbox is a single reduction gearbox.

12. A method of accessing batteries of a power wheelchair, comprising the steps of:

a) providing a wheelchair that includes:

a frame including a seat post;

a pair of opposing drive wheels;

a pair of pivoting assemblies, each one of the pivoting assemblies: (i) including a drive assembly and a front arm assembly, (ii) associated with one of the drive wheels, and (iii) pivotally connected to the frame;

each drive assembly including a motor and gearbox that are transversely mounted relative to the frame and operatively coupled to one of the drive wheels;

a battery compartment formed on the frame and located rearward of the drive assemblies; batteries located in the battery compartment; and

an articulating beam assembly including a transverse member, pair of legs, and a pair of rear wheel assemblies, the legs extend generally rearwardly from opposing ends of the transverse member to the rear wheel assemblies, the transverse member being pivotally coupled to the seat post forward of the batteries; and

b) accessing the batteries from the rear of the wheelchair between legs.

13. The method of claim 12 wherein the transverse member is generally parallel to the axis of rotation of the drive wheels.

14. A wheelchair comprising:

a frame;

a pair of opposing drive wheels;

a pair of pivoting assemblies, each one of the pivoting assemblies including a drive assembly and a front arm assembly, each one of the pivoting assemblies being associated with one of the drive wheels and pivotally connected to the frame;

each drive assembly including a motor, a gearbox, and a vertical plate to which the gearbox is affixed, the vertical plate including a surface to which the front arm is rigidly affixed;

a battery compartment formed on the frame and located rearward of the drive assemblies;

batteries located in the battery compartment; and

an articulating beam assembly including a transverse member, pair of legs, and a pair of rear wheel assemblies, the legs extending generally rearwardly from opposing ends of the transverse member to the rear wheel assemblies, the transverse member being pivotally coupled to the frame forward of the batteries;

wherein (i) each motor and gearbox is transversely mounted relative to the frame and operatively coupled to one of the drive wheels, (ii) a centerline of a pivot axis of the pivotal connection between the drive assembly and the frame has a vertical height that is approximately the same or less than the vertical height of an axis of rotation of the front wheel, and (iii) the battery compartment may be accessed from the rear of the wheelchair between the legs.

15. The wheelchair of claim 14 , wherein the frame comprises a seat post that is forward of the battery compartment, the transverse member of the articulating beam being pivotally connected to the seat post.

16. The wheelchair of claim 14 , wherein the articulating beam pivots about a substantially horizontal axis that is approximately perpendicular to the drive wheel axis of rotation.

17. The wheelchair of claim 14 , wherein each one of the pivoting assemblies includes a front wheel that is an anti-tip wheel.

18. The wheelchair of claim 17 , wherein the anti-tip wheel is suspended from a ground surface on which the wheelchair travels, the wheelchair further comprising a suspension capable of acting on the arm.

19. The wheelchair of claim 14 , wherein the front wheel is a castor wheel that is normally in contact with the ground surface on which the wheelchair travels.

20. The wheelchair of claim 14 , wherein the motor has a longitudinal axis that is transverse relative to the frame.

21. The wheelchair of claim 14 , wherein the gearbox is a single reduction gearbox.

22. A wheelchair comprising:

a frame including a seat post;

a pair of opposing drive wheels;

a pair of pivoting assemblies, each one of the pivoting assemblies including a drive assembly and a front arm assembly, each one of the pivoting assemblies being associated with one of the drive wheels and pivotally connected to the frame;

each drive assembly including a motor and gearbox that are mounted to the frame and operatively coupled to one of the drive wheels;

a battery compartment formed on the frame and located rearward of the seat post;

batteries for powering the motors; and

an articulating beam assembly including a transverse member, pair of legs, and a pair of rear wheel assemblies, the legs extending generally rearwardly from opposing ends of the transverse member to the rear wheel assemblies, the transverse member being pivotally coupled to the frame proximate to the seat post and forward of the battery compartment;

wherein (i) the batteries for powering the motors are all located in the battery compartment that is rearward of the drive assemblies, and (ii) the batteries for powering the motors may all be accessed from the rear of the wheelchair between the legs.

23. The wheelchair of claim 22 , wherein the transverse member is pivotally connected to the seat post.