Raiser seat

1. A riser seat for assisting a person from a sitting position to a standing position, comprising:

seat frame;

a seat comprising upper and lower surfaces, the seat being movable between first and second positions; and

a cam arm pivotably mounted with respect to the seat frame and having a camming surface movably engaged with the seat and the cam arm moves the seat along a movement profile between the first and second positions, wherein the camming surface defines the movement profile and the camming surface moves tangentially relative to the lower surface of the seat to move the seat between the first and second positions.

2. The riser seat of claim 1 wherein the camming surface is slidably engaged with the lower surface of the seat.

3. The riser seat of claim 1 wherein the cam arm is coupled to the seat frame at a pivot point, and the cam arm pivots about the pivot point.

4. The riser seat of claim 3 further comprising:

a gear coupled to the cam arm and coaxial with the pivot point; and

a rack in meshed engagement with the gear such that translation of the rack results in the cam arm pivoting about the pivot point.

5. The riser seat of claim 1 further comprising a linear actuator coupled to the seat frame at a front end of the seat frame, the linear actuator terminating in a top connection member that engages the lower surface of the seat at a front end of the seat, the linear actuator moving the front end of the seat between the first and second positions.

6. The riser seat of claim 5 further comprising a pivot that connects the top connection member to the seat, the seat pivoting about the pivot.

7. The riser seat of claim 6 wherein the cam arm and the linear actuator are independently movable.

8. The riser seat of claim 1 wherein the cam arm is a first cam arm and the riser seat further comprises a second cam arm pivotably mounted with respect to the seat frame, the second cam arm having a camming surface movably engaged with the seat and configured to move the seat between the first and second positions, wherein the camming surface moves tangentially relative to the lower surface of the seat when the seat is moved between the first and second positions.

9. The riser seat of claim 8 wherein the first cam arm and the second cam arm are coupled to the seat frame at a pivot point, and the first cam arm and the second cam arm pivot about the pivot point.

10. The riser seat of claim 8 wherein the first cam arm is coupled to the seat frame at a first pivot point and the first cam arm pivots about the first pivot point, and the second cam arm is coupled to the seat frame at a second pivot point and the second cam arm pivots about the second pivot point.

11. The riser seat of claim 1 further comprising a connection member on the cam arm, wherein the connection member engages the seat to maintain engagement between the camming surface and the lower surface of the seat.

12. The riser seat of claim 11 wherein the seat further comprises a guide track, the connection member of the cam arm engages the guide track of the seat.

13. The riser seat of claim 1 further comprising an aperture through the seat such that the seat functions as a commode.

14. The riser seat of claim 1 wherein the lower surface of the seat further comprises a track disposed along the lower surface, the camming surface contacting the track, the track facilitating the tangential movement of the camming surface relative to the lower seat.

15. The riser seat of claim 14 wherein the track comprises a friction reducing material.

16. The riser seat of claim 14 wherein the track comprises at least one roller.

17. The riser seat of claim 1 wherein the camming surface comprises a roller or bearing that engages the lower surface of the seat.

18. The riser seat of claim 1 wherein the cam arm further comprises a plurality of rotatably coupled cam sections.

19. The riser seat of claim 18 wherein the cam arm further comprises a center shaft and the plurality of rotatably coupled cam sections are mounted to the center shaft such that the cam sections rotate about the center shaft.

20. The riser seat of claim 18 wherein each of the plurality of cam sections further comprises a peg and a slot that receives a peg of an adjacent cam section, wherein the interaction of the peg and the slot restricts rotational movement of the plurality of cam sections.

21. A riser seat for assisting a person from a sitting position to a standing position, comprising:

a seat frame;

a seat comprising upper and lower surfaces, the seat being movable between first and second positions;

first and second cam arms pivotably mounted with respect to the seat frame, each of the first and second cam arms having a camming surface movably engaged with the seat wherein the camming surface moves tangentially relative to the lower surface of the seat when the seat is moved between the first and second positions; and

first and second linear actuators coupled to the seat frame, wherein each of the first and the second linear actuators engage the seat at a front end of the seat;

wherein coordinated movement of the first and the second cam arms and the first and the second linear actuators moves the seat between the first and second positions.

22. The riser seat of claim 21 wherein the first cam arm, the second cam arm, the first linear actuator, and the second linear actuator are each independently movable.

23. The riser seat of claim 22 further comprising a first pivot that connects the first linear actuator to the seat and a second pivot that connects the second linear actuator to the seat, the seat being pivotably moveable about the first pivot and the second pivot.

24. The riser seat of claim 23 wherein the coordinated movement of the first and second cam arms and the first and second linear actuators moves the seat along a movement profile wherein the movement profile lifts and tilts the seat.

25. The riser seat of claim 24 wherein the movement profile further pitches the seat to a first side of the seat.

26. The riser seat of claim 23 wherein the first cam arm is coupled to the seat frame at a first pivot point and the first cam arm moves about the first pivot point, and the second cam arm is coupled to the seat frame at a second pivot point and the second cam arm moves about the second pivot point.

27. A method using the riser seat of claim 21 to move a person sitting on the seat from a seated position to a standing position, comprising:

simultaneously moving the first and second linear actuators and the first and second cam arms to lift the person in a seated position;

maintaining a position of the first and second linear actuators; and

moving the first and second cam arms to tilt the person into a standing position.

28. The method of claim 27 further comprising:

simultaneously moving the first linear actuator and the first cam arm such that a first side of the seat is raised above a second side of the seat such as to pitch the seat in the direction of the second linear actuator and the second cam arm.

29. A riser seat for assisting a person from a sitting position to a standing position, comprising:

a seat frame;

a seat comprising upper and lower surfaces, the seat being movable between first and second positions; and

first, second, third, and fourth cam arms pivotably mounted with respect to the seat frame, each of the first, second, third, and fourth cam arms having a camming surface movably engaged with the seat wherein each of the camming surfaces move tangentially relative to the lower surface of the seat when the seat is moved between the first and second positions;

wherein coordinated movement of the first, second, third, and fourth cam arms moves the seat between the first and second positions.

30. The riser seat of claim 23 , wherein the first, second, third, and fourth cam arms are each independently movable.

31. The riser seat of claim 29 , further comprising a first pivot point that couples the first cam arm to the seat frame, a second pivot point that couples the second cam arm to the seat frame, a third pivot point that couples the third cam arm to the seat frame, and a fourth pivot point that couples the fourth cam arm to the seat frame.

32. The riser seat of claim 29 wherein the coordinated movement of the first, second, third, and fourth cam arms move the seat along a movement profile that lifts and tilts the seat.

33. The riser seat of claim 32 wherein the movement profile further pitches the seat to a first side of the seat.

34. A method of using the riser seat of claim 29 to move a person sitting on the seat from a seated position to a standing position, comprising:

simultaneously moving the first, second, third, and fourth cam arms to lift the person in a seated position;

maintaining a relative position of the first cam arm;

simultaneously moving the second, third, and fourth cam arms to lift the person;

maintaining a relative position of the second cam arm;

simultaneously moving the third and fourth cam arms to lift the person;

maintaining a relative position of the third cam arm; and

moving the fourth cam arm to tilt the person into a standing position.

35. The method of claim 34 , further comprising:

simultaneously moving the first, second, and third cam arms such that a first side of the seat is raised above a second side of the seat such as to pitch the seat in the direction of the fourth cam arm.

36. An adjustable position riser seat comprising:

a seat frame;

a seat comprising upper and lower surfaces, the seat being movable between first and second positions; and

a cam arm pivotably mounted with respect to the seat frame and having a camming surface movably engaged with the seat and configured to move the seat along a movement profile between the first and second positions, wherein the camming surface defines the movement profile and the camming surface moves tangentially relative to the lower surface of the seat to move the seat between the first and second positions.

37. An adjustable position riser seat comprising:

a seat frame;

a seat comprising upper and lower surfaces, the seat being movable between first and second positions;

a first cam arm pivotably mounted with respect to the seat frame and the first cam arm having a camming surface movably engaged with the seat and configured to move the seat between the first and second positions; and

a second cam arm pivotably mounted with respect to the seat frame and the second cam arm having a camming surface movably engaged with the seat and configured to move the seat between the first and second positions;

wherein the camming surfaces move tangentially relative to the lower surface of the seat when the seat is moved between the first and second positions.

38. The riser seat of claim 37 wherein the first cam arm and the second cam arm are coupled to the seat frame at a pivot point, and the first cam arm and the second cam arm pivot about the pivot point.

39. The riser seat of claim 37 wherein the first cam arm is coupled to the seat frame at a first pivot point and the first cam arm pivots about the first pivot point, and the second cam arm is coupled to the seat frame at a second pivot point and the second cam arm pivots about the second pivot point.