Interlock and surgical instrument including same

• US 20080167670A1
• Filed: 01/10/2007
• Published: 07/10/2008
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Inventors: Giordano, James R., Shelton, Frederick E.
• Granted Patent: US 7,721,936 B2
• Time in Patent Office: Days
• US Class Current: 606/167
• CPC Class Codes: A61B 17/07207 the staples being applied sequentially
• CPC Class Codes: A61B 2017/00022 Sensing or detecting at the treatment site
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2017/00734 battery operated
• CPC Class Codes: A61B 2017/07271 characterised by its cartridge
• CPC Class Codes: A61B 2017/07278 characterised by its sled or its staple holder
• CPC Class Codes: A61B 2017/07285 characterised by its cutter
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2090/0811 for the position of a particular part of an instrument with respect to the rest of the instrument, e.g. position of the anvil of a stapling instrument
• CPC Class Codes: A61B 2090/0814 Preventing re-use
• CPC Class Codes: A61B 90/361 Image-producing devices, e.g. surgical cameras

Abstract

A surgical instrument is disclosed. The instrument includes an end effector comprising a moveable cutting instrument to cut an object and a motor coupled to the end effector. The motor actuates the cutting instrument in response to a current therethrough, causing the cutting instrument to move between a proximal-most position and a distal-most position. The instrument includes an interlock coupled to the end effector and to the motor to prevent actuation of the cutting instrument based on the current through the motor.

Claims

1. A surgical instrument, comprising:

an end effector comprising a moveable cutting instrument to cut an object;

a motor coupled to the end effector, the motor to actuate the cutting instrument in response to a current therethrough, wherein actuation of the cutting instrument causes the cutting instrument to move between a proximal-most position and a distal-most position; and

an interlock coupled to the end effector and to the motor, the interlock to prevent actuation of the cutting instrument based on the current through the motor.

2. The instrument of claim 1, wherein the end effector further comprises:

a longitudinally extending channel, the channel having a proximal end and a distal end;

an anvil pivotally attached to the channel, wherein the object is positioned between the anvil and the channel;

a staple cartridge removably seated in the channel, the staple cartridge having a proximal end and a distal end;

a firing drive slot formed between the cartridge and the channel through which at least a portion of the cutting instrument passes when the cutting instrument is actuated; and

a sled disposed in the staple cartridge, wherein when the cutting instrument is actuated the sled is engaged by the cutting instrument and driven longitudinally through the staple cartridge from an unfired position located at the proximal end of the staple cartridge to a fired position located the distal end of the staple cartridge.

3. The instrument of claim 2, wherein the interlock comprises:

a blocking mechanism to prevent actuation of the cutting instrument, wherein the blocking mechanism is activated when the sled is not present in the unfired position; and

a lockout circuit to sense the current through the motor and to interrupt the current through the motor based on the sensed current.

4. The instrument of claim 3, wherein the lockout circuit is further to interrupt the current through the motor based on a position of the cutting instrument.

5. The instrument of claim 3, wherein the current through the motor increases when the blocking mechanism prevents the cutting instrument from advancing longitudinally through the channel.

6. The instrument of claim 3, wherein the blocking mechanism comprises at least one spring finger disposed in the channel.

7. The instrument of claim 3, wherein the blocking mechanism comprises at least one ramped hook springedly attached to the channel.

8. The instrument of claim 3, wherein the blocking mechanism is formed integrally with the staple cartridge and comprises at least one proximally projecting member, wherein the at least one member is movable between the firing drive slot and a recess in the staple cartridge.

9. The instrument of claim 3, wherein the lockout circuit comprises a current sensor to generate a first signal representative of the sensed current.

10. The instrument of claim 9, wherein the lockout circuit further comprises a current detection module to compare the first signal to a predetermined threshold signal.

11. The instrument of claim 10, wherein the current detection module comprises a micro processor.

12. The instrument of claim 10, wherein the lockout circuit further comprises a position sensor to determine a position of the cutting instrument.

13. The instrument of claim 12, wherein the lockout circuit further comprises a switch connected in series with the motor, the switch controllable to interrupt the current through the motor based on the position of the cutting instrument and the comparison of the first signal to the predetermined threshold signal.

14. The instrument of claim 13, wherein the switch is controllable to interrupt the current through the motor when the position of the cutting instrument is within a predetermined distance of the proximal-most position of the cutting instrument and when the first signal exceeds the predetermined threshold signal.

15. A method for preventing operation of a surgical instrument, the surgical instrument configured for removably receiving an expendable staple cartridge and comprising a moveable cutting instrument and a motor to actuate the cutting instrument in response to a current therethrough, the method comprising:

mechanically blocking actuation of the cutting instrument by the motor in the absence of an unexpended staple cartridge in the instrument;

detecting the current through the motor resulting from the blocked actuation of the cutting instrument; and

interrupting the current through the motor based on the detected current.

16. The method of claim 15, wherein detecting the current through the motor includes:

sensing the motor current;

generating a signal representative of the sensed motor current; and

comparing the generated signal to a threshold signal.

17. The method of claim 16, wherein interrupting the current through the motor includes interrupting the current when the generated signal exceeds the threshold signal.

18. The method of claim 17, wherein interrupting the current through the motor further includes interrupting the current based on a position of the cutting instrument.

19. A method of processing a surgical instrument, comprising:

obtaining the surgical instrument, wherein the surgical instrument comprises;

an end effector comprising a moveable cutting instrument to cut an object;

a motor coupled to the end effector, the motor to actuate the cutting instrument in response to a current therethrough, wherein actuation of the cutting instrument causes the cutting instrument to move between a proximal-most position and a distal-most position; and

an interlock coupled to the end effector and to the motor, the interlock to prevent actuation of the cutting instrument based on the current through the motor;

sterilizing the surgical instrument; and

storing the surgical instrument in a sterile container.