Obstacle traversing wheelchair
View Patent ↗A wheelchair suspension is provided. The wheelchair suspension includes a frame, a pivot arm, a front caster, a drive assembly, and a rear caster. The pivot arm is pivotally coupled to the frame. The front caster is coupled to the pivot arm. Movement of the drive assembly in a first direction causes the pivot arm to substantially remain in a first position. Movement of the drive assembly in a second direction urges the pivot arm away from the first position.
1. A wheelchair suspension comprising:
a frame;
a pivot arm pivotally coupled to the frame;
a front caster coupled to the pivot arm;
a drive assembly mounting bracket;
a rear caster coupled to the frame; and
wherein movement of the drive assembly mounting bracket with respect to the frame in a first direction causes the pivot arm to remain in substantially a first position; and
movement of the drive assembly mounting bracket with respect to the frame in a second direction urges the pivot arm away from the first position.
2. The wheelchair suspension of claim 1 wherein movement of the drive assembly mounting bracket with respect to the frame in the second direction pushes the pivot arm upward.
3. The wheelchair suspension of claim 1 wherein relative movement between the drive assembly mounting bracket and the pivot arm is dampened.
4. The wheelchair suspension of claim 3 wherein the relative movement between the drive assembly mounting bracket and the pivot arm is dampened by a spring.
5. The wheelchair suspension of claim 1 wherein the movement of the drive assembly mounting bracket with respect to the frame in the second direction relative to the frame pushes the pivot arm upward to urge the front caster away from a support surface.
6. The wheelchair suspension of claim 1 wherein the drive assembly mounting bracket is pivotally coupled to the frame.
7. The wheelchair suspension of claim 6 wherein the drive assembly mounting bracket is pivotally coupled to the pivot arm and the pivot arm is pivotally coupled to the frame.
8. The wheelchair suspension of claim 1 wherein movement of the drive assembly mounting bracket with respect to the frame in the second direction causes the pivot arm to move upward.
9. The wheelchair suspension of claim 1 wherein movement of the drive assembly mounting bracket with respect to the frame in the first direction comprises upward movement of the drive assembly and movement of the drive assembly in the second direction comprises downward movement of the drive assembly.
10. The wheelchair suspension of claim 1 wherein the pivot arm is coupled to the frame at a pivotal connection and force is applied by the drive assembly mounting bracket to the pivot arm between the pivotal connection and the front caster.
11. The wheelchair suspension of claim 10 wherein force applied by the drive assembly mounting bracket to the pivot arm causes the pivot arm to move upward.
12. The wheelchair suspension of claim 10 wherein movement of the drive assembly mounting bracket with respect to the frame in the second direction pushes the front caster upward.
13. A wheelchair suspension comprising:
a frame;
a seat supported by the frame;
a rear caster coupled to the frame;
a pair of suspension assemblies disposed on opposite sides of the frame, each suspension assembly comprising:
a pivot arm coupled to the frame;
a front caster coupled to the pivot arm;
a drive assembly mounting bracket;
wherein the movement of the drive assembly mounting bracket with respect to the frame in a first direction causes the pivot arm to remain in substantially a first position; and
movement of the drive assembly mounting bracket with respect to the frame in a second direction urges the pivot arm away from the first position.
14. The wheelchair suspension of claim 13 wherein movement of the drive assembly mounting bracket with respect to the frame in the second direction pushes the pivot arm upward.
15. The wheelchair suspension of claim 13 wherein relative movement between the drive assembly mounting bracket with respect to the frame and the pivot arm is dampened.
16. The wheelchair suspension of claim 15 wherein the relative movement between the drive assembly mounting bracket and the pivot arm is dampened by a spring.
17. The wheelchair suspension of claim 13 wherein the pivotal movement of the drive assembly mounting bracket with respect to the frame in the second direction relative to the frame pushes the pivot arm upward to urge the front caster away from a support surface to traverse an obstacle.
18. The wheelchair suspension of claim 13 wherein the drive assembly mounting bracket is pivotally coupled to the frame.
19. The wheelchair suspension of claim 18 wherein the drive assembly mounting bracket is pivotally coupled to the pivot arm and the front caster pivot arm is pivotally coupled to the frame.
20. The wheelchair suspension of claim 13 wherein movement of the drive assembly mounting bracket with respect to the frame in the second direction causes the pivot arm to move upward.
21. The wheelchair suspension of claim 13 wherein the movement of the drive assembly mounting bracket with respect to the frame in the first direction comprises upward movement of the drive assembly and movement of the drive assembly in the second direction comprises downward movement of the drive assembly.
22. The wheelchair suspension of claim 13 wherein the pivot arm is coupled to the frame at a pivotal connection and force is applied by the drive assembly to the pivot arm between the pivotal connection and the front caster.
23. The wheelchair suspension of claim 22 wherein force applied by the drive assembly mounting bracket to the pivot arm causes the pivot arm to move upward.
24. The wheelchair suspension of claim 22 wherein movement of the drive assembly mounting bracket with respect to the frame in the second direction pushes the front caster upward.
25. A wheelchair suspension comprising:
a frame;
a pivot arm pivotally coupled to the frame;
a front caster coupled to the pivot arm;
a drive assembly mounting bracket;
a rear caster coupled to the frame; and
a means for coupling the pivot arm and the front caster such that movement of the drive assembly mounting bracket with respect to the frame in a first direction causes the pivot arm to remain in substantially a first position; and
movement of the drive assembly mounting bracket with respect to the frame in a second direction urges the pivot arm away from the first position.
26. A wheelchair comprising:
a frame;
a front caster assembly comprising a pivot arm;
a drive assembly comprising a pivot bracket;
wherein movement of the drive assembly rivot bracket with respect to the frame in a first direction causes the rivot arm to remain in substantially a first position; and
movement of the drive assembly rivot bracket with respect to the frame in a second direction urges the rivot arm away from the first position.
27. The wheelchair of claim 26 further comprising a spring interposed between the pivot bracket and the pivot arm.
28. The wheelchair of claim 26 wherein the pivot bracket is directly coupled to the pivot arm.
29. A wheelchair comprising:
a frame;
a pivot arm having a first pivot coupling;
a front caster coupled to the pivot arm;
a drive assembly having a mount, wherein the mount includes a second pivot coupling;
a rear caster coupled to the frame; and
wherein movement of the drive assembly mount in a first rivot direction causes the pivot arm to remain in substantially a first position; and
movement of the drive assembly mount in a second rivot direction urges the pivot arm away from the first position.
30. The wheelchair suspension of claim 29 wherein movement of the drive assembly mount in the second rivot direction urges the pivot arm upward.
31. The wheelchair suspension of claim 29 wherein movement between the drive assembly mount and the pivot arm is dampened.
32. The wheelchair suspension of claim 31 wherein the movement between the drive assembly mount and the pivot arm is dampened by a resilient device.
33. The wheelchair suspension of claim 29 further comprising a deformable member in physical communication with the drive assembly mount and pivot arm.
34. A wheelchair suspension comprising:
a frame;
a pivot arm pivotally coupled to the frame;
a front caster coupled to the pivot arm;
a drive assembly mounting bracket;
a rear caster coupled to the frame; and
wherein movement of the drive assembly mounting bracket with respect to the pivot arm in a first direction causes the pivot arm to remain in substantially a first position; and
movement of the drive assembly mounting bracket with respect to the pivot arm in a second direction urges the pivot arm away from the first position.