Surgical machine and method for controlling and/or regulating a surgical machine

1. Surgical machine comprising:

a housing,

a surgical drive disposed in the housing,

a push-button unit with at least one actuating member mounted on the housing for movement in a direction of actuation for prescribing a rotational speed and/or a direction of rotation of the surgical machine,

a field generating unit for generating a magnetic field,

at least one actuating sensor coupled with the field generating unit for generating an actuation signal in response to a movement and/or a position of the actuating member, the generated actuation signal being correlated with a field strength and/or a change in the field generated by the field generating unit, which occurs as a result of a movement of the actuating member,

a field changing member for generating a change in the field acting at a location of the actuating sensor and generated by the field generating unit, which occurs as a result of a movement and/or a changed position of the actuating member,

wherein:

the drive and the housing are directly or indirectly connectable in a detachable manner, and

the actuating sensor and the field generating unit are fixedly disposed relative to each other.

2. Machine in accordance with claim 1 , wherein the push-button unit comprises a frame.

3. Machine in accordance with claim 1 , wherein the actuating sensor is a magnetic field sensor.

4. Machine in accordance with claim 3 , wherein the magnetic field sensor is a Hall sensor.

5. Machine in accordance with claim 1 , wherein the field changing member is at least partially magnetically polarizable and has a magnetic susceptibility χ m differing from zero.

6. Machine in accordance with claim 5 , wherein the field changing member is at least partially diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic or ferrimagnetic.

7. Machine in accordance with claim 5 , wherein the field changing member is a soft iron element.

8. Machine in accordance with claim 1 , wherein the field generating unit is a magnet.

9. Machine in accordance with claim 8 , wherein the magnet is a permanent magnet.

10. Machine in accordance with claim 8 , wherein the magnet is formed by a coil.

11. Machine in accordance with claim 1 , wherein the actuating sensor is disposed between poles of the field generating unit.

12. Machine in accordance with claim 11 , wherein the actuating sensor is disposed in a gap of a ring coil.

13. Machine in accordance with claim 1 , wherein a cross section of the field changing member varies in a direction of actuation of the actuating member.

14. Machine in accordance with claim 13 , wherein the cross section increases.

15. Machine in accordance with claim 1 , wherein the field generating unit is coupled by a return path system with the actuating sensor.

16. Machine in accordance with claim 15 , wherein the return path system is a magnetic return path system.

17. Machine in accordance with claim 1 , wherein the field generating unit, the return path system and the actuating sensor define a recess, and the field changing member is so disposed that it is at least partially introducible into the recess as a result of a movement of the actuating member.

18. Machine in accordance with claim 17 , wherein the recess has a substantially rectangular cross section.

19. Machine in accordance with claim 1 , wherein the actuating member carries the field changing member.

20. Machine in accordance with claim 1 , wherein the field generating unit is disposed on a power and control unit.

21. Machine in accordance with claim 1 , wherein:

the machine has at least two different operating modes,

a first operating mode position of the at least one actuating member being associated with a first operating mode, and

the at least one actuating member is rotatable about an axis of rotation from the first operating mode position to a second operating mode position, which is associated with a second operating mode of the machine, in order to switch the drive unit over from the first operating mode to the second operating mode.