Robotic electrosurgical device with disposable shaft

1. An apparatus for operating on tissue, comprising:

(a) an end effector;

(b) a shaft assembly extending proximally from the end effector along a longitudinal axis, wherein the shaft assembly includes a proximal end portion having a first coupling feature projecting radially outward therefrom about the longitudinal axis; and

(c) an interface assembly configured to removably couple with the shaft assembly for use with a robotic system, the interface assembly including:

(i) a proximal end,

(ii) a distal end, and

(iii) a first drive assembly having a first slot with a first proximal slot opening, wherein the first slot is configured to distally receive the first coupling feature of the shaft assembly through the first proximal slot opening to removably couple the first coupling feature to the first drive assembly, wherein the first drive assembly is configured to actuate the first coupling feature to thereby actuate the end effector,

wherein the shaft assembly is axially insertable into the proximal end of the interface assembly upon removably coupling the first coupling feature to the first drive assembly such that the end effector is configured to travel through the proximal end of the interface assembly and out through the distal end of the interface assembly,

wherein the first drive assembly further includes a first drive opening extending longitudinally therethrough, wherein the first drive opening is configured to distally receive the end effector and the shaft assembly such that the end effector is configured to travel through the first drive opening, and

wherein the first slot is positioned about the first drive opening such that the first slot extends radially inward in communication with the first drive opening to receive the radially outward projecting first coupling feature,

wherein the first slot is configured to receive the first coupling feature as a first bayonet fitting.

2. The apparatus of claim 1 , wherein the first drive opening has a proximal diameter and a distal diameter, and wherein the proximal diameter is larger than the distal diameter.

3. The apparatus of claim 1 , wherein the first drive assembly comprises a helical gear, wherein the helical gear is concentrically positioned about the first drive opening.

4. The apparatus of claim 3 , wherein the helical gear is configured to rotate the shaft assembly relative to the interface assembly.

5. The apparatus of claim 1 , wherein the proximal portion of the shaft assembly further includes a second coupling feature projecting radially therefrom about the longitudinal axis, wherein the second coupling feature is configured to move relative to the first coupling feature, wherein the interface assembly further includes a second drive assembly having a second slot with a second proximal slot opening, wherein the second slot is configured to distally receive the second coupling feature of the shaft assembly through the second proximal slot opening to removably couple the second coupling feature to the second drive assembly, wherein the second drive assembly is configured to actuate the second coupling feature to thereby further actuate the end effector.

6. The apparatus of claim 5 , wherein the second drive assembly further includes a second drive opening extending longitudinally therethrough, wherein the second drive opening is configured to distally receive the end effector and the shaft assembly such that the end effector is configured to travel through the second drive opening.

7. The apparatus of claim 6 , wherein the first drive opening and the second drive opening are coaxial to coaxially receive the shaft assembly along the longitudinal axis.

8. The apparatus of claim 6 , wherein the second slot is positioned about the second drive opening such that the second slot extends radially inward in communication with the second drive opening.

9. The apparatus of claim 6 , wherein the second drive assembly further includes a through slot extending longitudinally therethrough from a proximal through opening to a distal through opening, wherein the through slot is configured to receive the first coupling feature such that the first coupling feature passes through the through slot and the distal through opening to the first drive assembly for removably coupling the first coupling feature to the first drive assembly.

10. The apparatus of claim 9 , wherein the second slot and the through slot are positioned about the second drive opening.

11. The apparatus of claim 10 , wherein the second drive assembly comprises a tubular member, wherein the tubular member is concentrically positioned about the second drive opening.

12. The apparatus of claim 11 , the second slot is configured to receive the second coupling feature as a second bayonet fitting.

13. The apparatus of claim 5 , wherein the shaft assembly further includes an outer shaft and an inner shaft extending proximally from the outer shaft, wherein the inner shaft is translatable relative to the outer shaft, wherein the first coupling feature is positioned on the outer shaft, wherein the second coupling feature is positioned on the inner shaft proximal to the first coupling feature.

14. The apparatus of claim 13 , wherein the end effector further includes a first jaw and a second jaw pivotable relative to the first jaw, wherein the tubular member is configured to move the second jaw relative to the first jaw.

15. The apparatus of claim 13 , wherein the proximal portion of the shaft assembly further includes a third coupling feature and a fourth coupling feature projecting radially therefrom about the longitudinal axis, wherein the interface assembly further includes a third drive assembly and a fourth drive assembly, wherein the third and fourth drive assemblies are configured to removably couple with the third and fourth coupling features, respectively, such that the third and fourth drive assemblies are configured to respectively actuate the third and fourth coupling features to thereby further actuate the end effector.

16. An apparatus for operating on tissue, comprising:

(a) an end effector;

(b) a shaft assembly extending proximally from the end effector along a longitudinal axis, wherein the shaft assembly includes a proximal end portion having a first coupling feature projecting radially outward therefrom about the longitudinal axis and a second coupling feature projecting radially outward therefrom about the longitudinally axis, wherein the shaft assembly further includes an outer member and an inner member, wherein the outer member is configured to movably receive the inner member and wherein the first and second coupling features extend from the outer and inner members, respectively, and wherein the second coupling feature is configured to move relative to the first coupling feature to thereby actuate the inner member relative to the outer member; and

(c) an interface assembly configured to removably couple with the shaft assembly for use with a robotic system, the interface assembly including:

(i) a proximal end,

(ii) a distal end,

(iii) a first drive assembly having a first slot with a first proximal slot opening, wherein the first slot is configured to distally receive the first coupling feature of the shaft assembly through the first proximal slot opening to removably couple the first coupling feature to the first drive assembly, wherein the first drive assembly is configured to actuate the first coupling feature to thereby actuate the end effector, and

(iv) a second drive assembly having a second slot with a second proximal slot opening, wherein the second slot is configured to distally receive the second coupling feature of the shaft assembly through the second proximal slot opening to removably couple the second coupling feature to the second drive assembly, wherein the second drive assembly is configured to actuate the second coupling feature to thereby further actuate the end effector,

wherein the shaft assembly is axially insertable into the proximal end of the interface assembly upon removably coupling the first coupling feature to the first drive assembly such that the end effector is configured to travel through the proximal end of the interface assembly and out through the distal end of the interface assembly.

17. The apparatus of claim 16 , wherein the second coupling feature is positioned proximal relative to the first coupling feature.

18. An apparatus for operating on tissue, comprising:

(a) an end effector;

(b) a shaft assembly extending proximally from the end effector along a longitudinal axis, wherein the shaft assembly includes a proximal end portion having a first coupling feature projecting radially therefrom about the longitudinal axis; and

(c) an interface assembly configured to removably couple with the shaft assembly for use with a robotic system, the interface assembly including:

(i) a proximal end,

(ii) a distal end, and

(iii) a first drive assembly having a first slot with a first proximal slot opening, wherein the first slot is configured to distally receive the first coupling feature of the shaft assembly through the first proximal slot opening to removably couple the first coupling feature to the first drive assembly, wherein the first drive assembly is configured to actuate the first coupling feature to thereby actuate the end effector,

wherein the shaft assembly is axially insertable into the proximal end of the interface assembly upon removably coupling the first coupling feature to the first drive assembly such that the end effector is configured to travel through the proximal end of the interface assembly and out through the distal end of the interface assembly,

wherein the shaft assembly further includes an outer shaft and an inner shaft extending proximally from the outer shaft, wherein the inner shaft is movable relative to the outer shaft, and wherein the first coupling feature extends from the outer shaft or inner shaft and is configured to actuate the outer and inner shafts relative to each other.

19. The apparatus of claim 18 , wherein the first coupling feature extends from the outer shaft.