Surgical device, in particular for minimally invasive surgery

1. A surgical device, in particular for minimally invasive surgery, provided with:

a shaft having a distal end equipped to mount a surgical instrument on the distal end, said distal end of the shaft comprising inserts, and a proximal end equipped for handling the instrument,

wherein the shaft is at least in part hollow, and

wherein the surgical instrument is equipped to be mounted on the inserts, which are longitudinally movable in the shaft parallel to the longitudinal axis of the shaft,

wherein the inserts are provided diametrically opposed to each other within the shaft,

wherein the shaft comprises an outer tube and an inner tube which are rotatable in opposite directions with respect to the longitudinal axis of the shaft, and the inserts are coupled to the outer tube and the inner tube so as to convert rotational movement of said tubes into longitudinal movement of the inserts,

wherein the inserts have one or more protrusions cooperating with slits in the outer tube and slits in the inner tube so as to define the longitudinal position of the inserts with respect to the shaft,

wherein the slits in the outer tube and the slits in the inner tube are provided at a predetermined angle with respect to each other so as to arrange that each protrusion of the one or more protrusions on the inserts has a single position at which each protrusion is able to protrude through both a slit in the inner tube and a slit in the outer tube.

2. The surgical device according to claim 1 , wherein the inner tube snugly fits into the outer tube.

3. The surgical device according to claim 1 or 2 , wherein rotation of the inner tube and the outer tube with respect to each other causes each protrusion on the inserts that protrudes through the angled slits in the inner tube and outer tube respectively to translate in the shaft's longitudinal direction.

4. The surgical device according to claim 1 , wherein the one or more protrusions on the inserts are provided on resilient parts of said inserts so as to arrange that the one or more protrusions can be depressed and removed from the slits in the shaft.

5. The surgical device according to claim 1 , wherein at the proximal end the device has means for rotational movement of the inner tube and outer tube of the shaft with respect to each other.

6. The surgical device according to claim 5 , wherein the means for rotational movement of the inner tube and outer tube comprise a differential gear coupled at its opposite ends with the inner tube and outer tube respectively.

7. A shaft for a surgical instrument, comprising:

a proximal end and a distal end equipped to mount the surgical instrument thereon,

wherein the shaft is at least in part hollow and is equipped to receive inserts diametrically opposed to each other within said shaft, and

wherein the surgical instrument is mounted or mountable on said inserts, and wherein the shaft is arranged such that the inserts are longitudinally movable in said shaft parallel to the longitudinal axis of the shaft,

wherein the shaft comprises an outer tube and an inner tube which are rotatable in opposite directions with respect to the longitudinal axis of the shaft, and the inserts are coupled to the outer tube and the inner tube so as to convert rotational movement of said tubes into longitudinal movement of the inserts,

wherein the inserts have one or more protrusions cooperating with slits in the outer tube and slits in the inner tube so as to define the longitudinal position of the inserts with respect to the shaft, wherein the slits in the outer tube and the slits in the inner tube are provided at a predetermined angle with respect to each other so as to arrange that each protrusion of the one or more protrusions on the inserts has a single position at which each protrusion is able to protrude through both a slit in the inner tube and a slit in the outer tube.

8. The shaft according to claim 7 , wherein the inner tube snugly fits into the outer tube.

9. The shaft according to claim 7 , wherein the slits are provided in the outer tube and inner tube of the shaft.

10. The shaft according to claim 7 , wherein rotation of the inner tube and the outer tube with respect to each other causes each protrusion on the inserts that protrudes through the angled slits in the inner tube and outer tube respectively to translate in the shaft's longitudinal direction.

11. The shaft according to claim 7 , wherein the one or more protrusions on the inserts are provided on resilient parts of said inserts so as to arrange that the one or more protrusions can be depressed and removed from the slits in the shaft.

12. The shaft according to claim 7 , wherein at the proximal end the shaft is connectable to means for rotational movement of the inner tube and outer tube of the shaft with respect to each other.