Bi-modal ankle-foot device

• US 20100030343A1
• Filed: 07/28/2009
• Published: 02/04/2010
• Est. Priority Date: 07/31/2008
• Status: Active Grant

• Current Assignee: Northwestern University
• Original Assignee: Northwestern University
• Inventors: Hansen, Andrew H., Childress, Dudley S.
• Granted Patent: US 8,764,850 B2
• Time in Patent Office: Days
• US Class Current: 623/47
• CPC Class Codes: A61F 2/6607 Ankle joints
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61F 2002/30359 Pyramidally- or frustopyramidally-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30476 locked by an additional locking mechanism
• CPC Class Codes: A61F 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/5001 Cosmetic coverings
• CPC Class Codes: A61F 2002/5003 having damping means, e.g. shock absorbers
• CPC Class Codes: A61F 2002/5009 having two or more elastomeric blocks
• CPC Class Codes: A61F 2002/5041 having bearing bushes between the rotating parts
• CPC Class Codes: A61F 2002/5043 with rotation-limiting stops, e.g. projections or recesses
• CPC Class Codes: A61F 2002/5055 Reinforcing prostheses by embedding particles or fibres during moulding or dipping, e.g. carbon fibre composites
• CPC Class Codes: A61F 2002/5056 Laminates, i.e. layered products
• CPC Class Codes: A61F 2002/5075 Multiple spring systems including two or more helical springs
• CPC Class Codes: A61F 2002/5078 2-D spiral springs
• CPC Class Codes: A61F 2002/6621 Toes
• CPC Class Codes: A61F 2002/665 Soles
• CPC Class Codes: A61F 2002/6818 for braking
• CPC Class Codes: A61F 2002/6845 Clutches
• CPC Class Codes: A61F 2002/6854 for locking or unlocking a joint
• CPC Class Codes: A61F 2002/701 : operated by electrically controlled means, e.g. solenoids or torque motors
• CPC Class Codes: A61F 2002/7615 : Measuring means
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit

Abstract

A bi-modal ankle-foot device that provides a curved effective shape appropriate for walking and a flattened effective shape for standing. The bi-modal ankle-foot device includes a foot piece and a lockable ankle joint connected to the flat foot piece, the ankle joint and foot piece cooperating to provide a curved shape for walking when the ankle joint is unlocked and to provide a flattened shape for standing when the ankle joint is locked.

Claims

1. A bi-modal ankle-foot device, comprising a foot piece and a lockable ankle joint connected to the foot piece, the ankle joint and foot piece cooperating to provide a curved effective shape for walking when the ankle joint is unlocked and to provide a flattened foot shape for standing when the ankle joint is locked.

2. The device of claim 1 which provides a curved effective foot shape for walking determined by cooperation of the foot piece with one or more resilient elements when the joint is unlocked.

3. The device of claim 2 wherein the curved effective shape comprises a circular rocker foot shape.

4. The device of claim 2 wherein the one or more resilient elements reside between the foot piece and an upper shank connector element that is connected to an artificial limb.

5. The device of claim 1 that includes a rotatable pin at the ankle joint and the axis of rotation of the pin is locked for standing.

6. The device of claim 5 wherein a shank connector element is connected to a foot connector element by a pin joint having the pin.

7. The device of claim 5 including a locking mechanism to lock the axis of rotation of the pin.

8. The device of claim 7 wherein the locking mechanism comprises a wrap spring clutch disposed on the pin to lock the pin joint for standing.

9. The device of claim 8 including a cam between control tangs of the wrap clutch spring.

10. The device of claim 9 wherein the cam spreads the control tangs to unlock the pin axis of rotation and the cam allows the control tangs to close to lock the pin axis of rotation.

11. The device of claim 9 wherein the cam is operated by a cable by the user of the device.

12. A bi-modal ankle-foot prosthetic or orthotic device, comprising a foot piece and an ankle joint connected to the foot piece wherein the ankle joint is unlockable to cooperate with the foot piece to provide a curved shape for walking and wherein the ankle joint is lockable to provide a flattened shape for standing.

13. The device of claim 12 which provides a curved effective shape for walking determined by cooperation of the foot piece with one or more resilient elements when the ankle joint is unlocked.

14. The device of claim 13 wherein the one or more resilient elements reside between the foot piece and an upper shank connector element that is connected to an artificial limb.

15. The device of claim 12 that includes rotatable pin at the ankle joint and the axis of rotation of the pin is locked for standing.

16. The device of claim 15 wherein the ankle joint comprises a shank connector element connected to foot connector element by the pin.

17. The device of claim 15 including a wrap spring clutch disposed on the pin to lock its axis of rotation for standing.

18. The device of claim 16 including a cam between control tangs of the wrap clutch spring.

19. The device of claim 17 wherein the cam spreads the control tangs to unlock the pin axis of rotation and the cam allows the control tangs to close to lock the pin axis of rotation.

20. The device of claim 18 wherein the cam is operated by a cable by the user of the device.

21. A method of controlling mode of movement of an ankle-foot joint, comprising unlocking the ankle joint to enable it to cooperate with a foot piece to provide a curved shape for walking and locking the ankle joint to provide a flattened shape for standing.