Jaw Closure Detection System

• US 20090261804A1
• Filed: 04/07/2009
• Published: 10/22/2009
• Est. Priority Date: 04/22/2008
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Inventors: Wham, Robert H., McKenna, Nicole
• Granted Patent: US 8,357,158 B2
• Time in Patent Office: Days
• US Class Current: 324/71.100
• CPC Class Codes: A61B 17/29 Forceps for use in minimally invasive surgery
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 18/1445 at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod
• CPC Class Codes: A61B 18/1447 wherein sliding surfaces cause opening/closing of the end effectors
• CPC Class Codes: A61B 2017/2926 Details of heads or jaws
• CPC Class Codes: A61B 2018/0063 Sealing
• CPC Class Codes: A61B 2090/067 for measuring angles

Abstract

A jaw angle detection system for an end effector assembly includes a first electrical contact that connects to a first jaw member and connects to a generator. A sensor connects to a second jaw member (or an actuator) and connects to the generator, and configured to move relative to the first electrical contact upon movement of the second jaw member (or the actuator) when the first and second jaw members are moved to close about tissue disposed therebetween. Information relating to the position of the sensor relative to the first electrical contact is relayed back to the generator to determine an angle between the first and second jaw members.

Claims

1. A jaw angle detection system for an end effector assembly, comprising:

a first electrical contact associated with a first jaw member and adapted to connect to one of a controller and a generator; and

a sensor associated with one of a second jaw member and an actuator and adapted to connect to one of the controller and the generator, the sensor configured to move relative to the first electrical contact upon movement of one of the respective second jaw member and the actuator when the first and second jaw members are moved to close about tissue disposed therebetween, wherein information relating to the position of the sensor relative to the first electrical contact is relayed back to one of the controller and the generator to determine an angle between the first and second jaw members.

2. A jaw angle detection system according to claim 1, wherein the sensor includes a series of resistors.

3. A jaw angle detection system according to claim 2, wherein the sensor includes a voltage divider network.

4. A jaw angle detection system according to claim 1, wherein the sensor includes a second electrical contact that is positioned to conduct a signal back to one of the controller and the generator when the second electrical contact electrically connects to the first electrically contact upon the jaw members closing about tissue past a threshold angle.

5. A jaw angle detection system according to claim 2, wherein the relative position of the first electrical contact relative to the sensor is represented in binary code.

6. A jaw angle detection system according to claim 1, wherein the sensor includes a variable capacitor.

7. A jaw angle detection system according to claim 6, wherein the variable capacitor includes first and second conductive rings, the first conductive ring fixed relative to the second conductive ring.

8. A jaw angle detection system, comprising:

first and second jaw members;

first and second conductors adapted to connect to a capacitive sensing circuit of a generator, the first conductor fixed relative to the second conductor, the second conductor moveable relative to the first conductor upon movement of the jaw members from a first spaced position relative to one another to a second position closer to one another; and

wherein information relating to the position of the second conductor relative to the first conductor is relayed back to the capacitive sensing circuit to determine an angle between the first and second jaw members.

9. A jaw angle detection system according to claim 8, wherein the first and second conductors are conductive rings.

10. A jaw angle detection system according to claim 8, wherein the second conductor is attached to a drive rod of an endoscopic electrosurgical forceps.

11. A jaw angle detection system according to claim 8, wherein the second conductor is attached to a movable jaw member of a unilateral endoscopic electrosurgical forceps.

12. A jaw angle detection system, comprising:

first and second jaw members each having proximally extending flanges adapted to connect to an energy source for conducting energy through tissue held between jaw members;

a conductor disposed on the proximal flange of the first jaw member; and

a variable resistor disposed on the proximal flange of the second jaw member in opposing relation to the conductor, the first conductor and the variable resistor adapted to relay a signal to a sensing circuit of the generator, wherein movement of the jaw members from an open spaced apart position to a closed position causes the conductor to move across the variable resistor and vary the signal relayed back to the sensing circuit to determine an angle between the first and second jaw members.

13. A jaw angle detection system according to claim 12, wherein the variable resistor is disposed in a port defined in the second jaw member, the port being configured to mechanically receive the conductor therein.

14. A jaw angle detection system according to claim 12, wherein the jaw detector is attached to the jaw members of an open electrosurgical forceps.

15. A jaw angle detection system according to claim 12, wherein the variable resistor includes a series of resistors.

16. A jaw angle detection system according to claim 12, wherein the variable resistor includes a voltage divider network.

17. A jaw angle detection method, comprising:

sensing a position of a first jaw member relative to a second jaw member of an end effector assembly;

conducting a signal representative of the sensed position back to one of a controller and a generator;

determining an angle between the first and second jaw members based on the signal; and

modifying energy delivery to the jaw members based on the determined angle.

18. A jaw angle detection method according to claim 17, further comprising providing information to a user based on the determined angle, the information selected from the group consisting of a tissue thickness, a rate of closure of the jaw members, a seal quality, and a re-grasp condition.