SURGICAL STAPLER HAVING FORCE-BASED MOTOR CONTROL

• US 20170079643A1
• Filed: 09/23/2015
• Published: 03/23/2017
• Est. Priority Date: 09/23/2015
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery LLC (Johnson & Johnson)
• Inventors: Yates, David C., Shelton, IV, Frederick E., Overmyer, Mark D., Leimbach, Richard L., Harris, Jason L.
• Granted Patent: US 10,363,036 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 17/07207 the staples being applied sequentially
• CPC Class Codes: A61B 2017/00017 Electrical control of surgical instruments
• CPC Class Codes: A61B 2017/00137 Details of operation mode
• CPC Class Codes: A61B 2017/00398 using powered actuators, e.g. stepper motors, solenoids
• CPC Class Codes: A61B 2017/0046 with a releasable handle; with handle and operating part separable for prosthetic joint-implanting tools A61F2/4603
• CPC Class Codes: A61B 2017/00486 Adaptors for coupling parts with incompatible geometries
• CPC Class Codes: A61B 2017/00734 battery operated
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: H02P 7/00 Arrangements for regulating or controlling the speed or torque of electric DC motors

Abstract

A surgical stapler. The surgical stapler includes a drive system, a handle assembly, an electric motor, a battery and a control system. The drive system includes a movable drive member. The handle assembly includes a frame configured to support the movable drive member. The electric motor is mechanically coupled to the drive system. The battery is electrically couplable to the electric motor. The control system is electrically connected to the electric motor and includes a sensor positioned on the frame. The control system is configured to control the electric motor based on a force applied to the frame by the movable drive member.

Claims

1. A surgical stapler, comprising:

a drive system comprising a movable drive member;

a handle assembly comprising a frame configured to support the movable drive member therein;

an electric motor mechanically coupled to the drive system;

a battery electrically couplable to the electric motor; and

a control system electrically connected to the electric motor, wherein the control system comprises a sensor positioned on the frame, and wherein the control system is configured to control the electric motor based on a force applied to the frame by the movable drive member.

2. The surgical stapler of claim 1, wherein the sensor comprises a strain gauge.

3. The surgical stapler of claim 1, wherein the sensor is positioned on an exterior surface of the frame.

4. The surgical stapler of claim 1, wherein the sensor is configured to sense the force applied to the frame by the movable drive member.

5. The surgical stapler of claim 1, wherein the control system further comprises a plurality of sensors positioned on the frame.

6. A surgical stapler, comprising:

a drive system comprising a movable drive member;

a handle assembly comprising a frame, wherein the frame defines a receptacle configured to support the movable drive member therein;

an electric motor mechanically coupled to the drive system;

a battery electrically couplable to the electric motor; and

a control system electrically connected to the battery, wherein the control system comprises a sensor positioned on the receptacle, and wherein the control system is configured to control the electric motor based on a force applied to the receptacle by the movable drive member.

7. The surgical stapler of claim 6, wherein the sensor comprises a strain gauge.

8. The surgical stapler of claim 6, wherein the sensor is configured to sense the force applied to the receptacle by the movable drive member.

9. The surgical stapler of claim 6, wherein the control system further comprises a plurality of sensors positioned on the receptacle.

10. A surgical stapler, comprising:

a drive system comprising;

a movable driving member;

a gear mechanically coupled with the movable driving member; and

a shaft connected to the gear;

a handle assembly comprising a bushing block configured to support the shaft;

an electric motor mechanically coupled to the drive system;

a battery electrically couplable to the electric motor; and

a control system electrically connected to the electric motor, wherein the control system comprises a sensor positioned on the bushing block and is configured to control the electric motor based on a force applied to the bushing block by the drive system.

11. The surgical stapler of claim 10, wherein the sensor comprises a strain gauge.

12. The surgical stapler of claim 10, wherein the sensor is configured to sense the force applied to the bushing block by the drive system.

13. The surgical stapler of claim 10, wherein:

the handle assembly further comprises a second bushing block configured to support the shaft; and

the control system further comprises a second sensor positioned on the second bushing block.

14. A surgical stapler, comprising:

a drive system comprising;

a movable drive member;

a gear mechanically coupled with the movable drive member; and

a shaft connected to the gear;

a handle assembly comprising a bushing block configured to support the shaft, wherein the bushing block comprises a three-layer bushing;

an electric motor mechanically coupled to the drive system;

a battery electrically couplable to the electric motor; and

a control system electrically connected to the electric motor, wherein the control system comprises a sensor coupled to the three-layered bushing, and wherein the control system is configured to control the electric motor based on a force applied to the three-layer bushing by the drive system.

15. The surgical stapler of claim 14, wherein the sensor is configured to sense a compression force applied to the three-layer bushing by the drive system.

16. The surgical stapler of claim 14, wherein:

the handle assembly further comprises a second bushing block configured to support the shaft, wherein the second bushing block comprises a second three-layer bushing; and

the control system further comprises a second sensor coupled to the second three-layer bushing.

17. A surgical stapler, comprising:

a drive system comprising;

a movable rack;

a gear mechanically coupled with the movable rack; and

a shaft connected to the gear;

a magnet connected to an end of the shaft;

a handle assembly comprising a frame configured to support the shaft;

an electric motor mechanically coupled to the drive system;

a battery electrically couplable to the electric motor; and

a control system electrically connected to the electric motor, wherein the control system comprises an array of sensors surrounding the magnet, and wherein the control system is configured to control the electric motor based on a force applied to shaft.

18. The surgical stapler of claim 17, wherein the array of sensors comprises an array of Hall-effect sensors.

19. The surgical stapler of claim 17, wherein the array of sensors are configured to sense a bending of the end of the shaft.

20. A method for limiting an impact force applied by a surgical stapler, the method comprising:

reading mass values and stiffness values for components of a system from one or more memories of the surgical stapler;

reading maximum force values from one or more memories for each state of the surgical stapler;

determining a current state of the surgical stapler; and

controlling an electric motor of the surgical stapler to limit the impact force applied by an end effector the surgical stapler based on the maximum force values for the determined state of the surgical stapler.

21. The method of claim 20, wherein reading the mass values and stiffness values comprises reading the values from at least one of the following:

a memory in a handle assembly of the surgical stapler; and

a memory in a shaft assembly of the surgical stapler.

22. The method of claim 20, wherein reading the maximum force values comprises reading at least one of the following:

a maximum force value for a clamped state of the surgical stapler;

a maximum force value for an unclamped state of the surgical stapler;

a maximum force value for an articulated state of the surgical stapler; and

a maximum force value for a firing state of the surgical stapler.

23. The method of claim 20, further comprising determining an overall mass value and an overall stiffness value for at least one of the following:

a closure system of the surgical stapler; and

a firing system of the surgical stapler.

24. The method of claim 23, wherein controlling the electric motor comprises, for the determined state of the surgical stapler, controlling the electric motor such that the velocity of one of the system components is less than or equal to the maximum force value for the determined state of the surgical stapler divided by a square root of a product of the overall mass value and the overall stiffness value for the system of the surgical stapler.

25. The method of claim 23, further comprising determining at least one of the following after the state of the surgical stapler is changed:

another overall mass value for the system of the surgical stapler; and

another overall stiffness value for the system of the surgical stapler.