Connection adapter
A connection adapter between a rigid transcutaneous implant can be anchored intracorporeally in a femoral stump, and a part of an extracorporeal orthopaedic knee joint. The connection adapter comprises a first coupling part for connection to the transcutaneous implant and a second coupling part for connection to the knee joint. The second coupling can be connected releasably to the first coupling part. A safety coupling is arranged in the interior of the second coupling part and transfers a torsional moment between the first coupling part and the second coupling part and slips through when an adjustable maximum value of the torsional moment is exceeded.
1. Connection adapter between a rigid transcutaneous implant, which can be anchored intracorporeally in a femoral stump, and a part of an extracorporeal orthopaedic knee joint, said connection adapter comprising a first coupling part for connection to the transcutaneous implant and a second coupling part for connection to the knee joint, the second coupling part being releasably connectable to the first coupling part characterized by a releasing safety coupling which is arranged inside the second coupling part, transfers a torsional moment between the first coupling part and the second coupling part, slides through when an adjustable maximum value of the torsional moment is exceeded, and is formed of a torsion disc fixed in the second coupling part from which torsion disc at least one shearing pin extends and engages with corresponding sockets in an end face of a sleeve that is in turn connectable to the first coupling part.
2. Connection adapter according to claim 1 , wherein the maximum value of the torsional moment is adjustable in the range from 5 to 35 Nm.
3. Connection adapter according to claim 1 , wherein the torsional moment is transferable without play up to the maximum value.
4. Connection adapter according to claim 1 , wherein the maximum value of the torsional moment to be transferred is adjustable via the selection of material, shape or arrangement of a plurality of shearing pins.
5. Connection adapter according to claim 1 , wherein the shearing pins consist of slightly deformable material.
6. Connection adapter according to claim 5 , wherein the material is copper.
7. Connection adapter according to claim 5 , wherein the material is brass.
8. Connection adapter according to claim 4 , wherein a plurality of shearing pins are provided with notches of different depths.
9. Connection adapter according to claim 4 , wherein a plurality of shearing pins are arranged on segments of a circle on the torsion disc.
10. Connection adapter according to claim 1 , wherein the at least one shearing pin is replaceable with another.
11. Connection adapter according to claim 1 , wherein a tensible tension spring is articulated to the second coupling part, ensures that the components are held together when tensioned and transfers the torsional moment without play by pressing the sleeve against the torsion disc, while enclosing the at least one shearing pin.
12. Connection adapter according to claim 11 , wherein the tension spring is configured as a clamp clip.
13. Connection adapter according to claim 1 , wherein the first coupling part is a double cone and the sleeve is a conical sleeve.
14. Connection adapter according to claim 2 , wherein the torsional moment is transferable without play up to the maximum value.
15. Connection adapter according to claim 5 , wherein a plurality of shearing pins are provided with notches of different depths.
16. Connection adapter according to claim 6 , wherein a plurality of shearing pins are provided with notches of different depths.
17. Connection adapter according to claim 7 , wherein a plurality of shearing pins are provided with notches of different depths.
18. Connection adapter according to claim 5 , wherein a tensible tension spring is articulated to the second coupling part, ensures that the components are held together when tensioned and transfers the torsional moment without play by pressing the sleeve against the torsion disc, while enclosing the at least one shearing pin.
19. Connection adapter according to claim 6 , wherein a tensible tension spring is articulated to the second coupling part, ensures that the components are held together when tensioned and transfers the torsional moment without play by pressing the sleeve against the torsion disc, while enclosing the at least one shearing pin.
20. Connection adapter according to claim 7 , wherein a tensible tension spring is articulated to the second coupling part, ensures that the components are held together when tensioned and transfers the torsional moment without play by pressing the sleeve against the torsion disc, while enclosing the at least one shearing pin.