Trigger lockout mechanism

• US 9,314,292 B2
• Filed: 10/23/2012
• Issued: 04/19/2016
• Est. Priority Date: 10/24/2011
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery LLC (Johnson & Johnson)
• Inventors: Trees, Gregory A., Stewart, Randolph, Chan, Wai T., Jackson, Thomas B.
• Primary Examiner(s): Stoklosa, Joseph
• Assistant Examiner(s): Fowler, Daniel
• Application Number:
  US13/658,792
• Publication Number:
  US 20130123782A1
• Time in Patent Office: 1,274 Days
• Field of Search: 606 51- 52
• US Class Current: 1/1
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• 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 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2017/00115 with audible or visual output
• CPC Class Codes: A61B 2018/00196 reciprocating lengthwise
• CPC Class Codes: A61B 2018/00595 Cauterization
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/0072 Current
• CPC Class Codes: A61B 2018/00726 Duty cycle
• CPC Class Codes: A61B 2018/00732 Frequency
• CPC Class Codes: A61B 2018/00767 Voltage
• CPC Class Codes: A61B 2018/00827 Current
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/00892 Voltage
• CPC Class Codes: A61B 2018/00916 with means for switching or controlling the main function of the instrument or device
• CPC Class Codes: A61B 2018/00922 by switching or controlling the treatment energy directly within the hand-piece
• CPC Class Codes: A61B 2018/1226 powered by a battery
• CPC Class Codes: A61B 2018/1286 having a specific transformer
• CPC Class Codes: A61B 2018/1455 : having a moving blade for cutting tissue grasped by the jaws
• CPC Class Codes: F16B 2/20 : Clips, i.e. with gripping action effected solely by the inherent resistance to deformation of the material of the fastening
• CPC Class Codes: H02J 7/00 : Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y10T 74/20666 : Lever engaging

Abstract

A medical instrument includes a housing, an RF generation circuit activation button coupled to an activation button lever supported by the housing. The activation button lever includes a top surface, the activation button lever rotatable about an activation button pivot point. A cutting blade is operably coupled to a sheath. A control lever is supported by the housing and pivotally coupled to a trigger lever including a projection to engage the top surface of the activation button lever and to control the actuation of the cutting blade by actuating the sheath in a distal direction by rotatably moving the control lever proximally about a trigger pivot point. The top surface of the activation button lever and the projection of the trigger lever remain engaged to prevent actuation of the cutting blade until the activation button is fully rotatably moved proximally about the activation button pivot.

Claims

1. A medical instrument, comprising:

a housing;

at least one electrical contact;

a radio frequency (RF) generation circuit configured to be operated by a battery and operable to generate an RF drive signal and to provide the RF drive signal to the at least one electrical contact;

an activation button coupled to an activation button lever supported by the housing, the activation button controls the activation of the RF generation circuit to apply the RF drive signal to the at least one electrical contact, the activation button lever comprising a top surface, the activation button lever rotatable about an activation button pivot point;

a cutting blade operably coupled to a sheath; and

a control lever supported by the housing and pivotally coupled to a trigger lever comprising a projection to engage the top surface of the activation button lever, the control lever is operable to control the actuation of the cutting blade by actuating the sheath in a distal direction when the control lever is rotatably moved proximally about a trigger pivot point;

wherein the top surface of the activation button lever and the projection of the trigger lever remain engaged to prevent actuation of the cutting blade until the activation button is fully rotatably moved proximally about the activation button pivot to activate the RF generation circuit such that the cutting blade is locked out until the RF generation circuit is activated.

2. The medical instrument according to claim 1, wherein when the activation button is fully engaged in the proximal direction, the activation button lever rotates about the activation button pivot point to release the top surface from the projection allowing the projection to slidably rotate past a surface of the activation button lever as the trigger lever slidably rotates about the trigger pivot point as the control lever is squeezed proximally.

3. The medical instrument according to claim 1, further comprising a torsion spring coupled to the activation button lever to apply a distal force to the activation button.

4. The medical instrument according to claim 3, comprising a second trigger lever supported by the housing, the second trigger lever comprising a first end that defines a pin slot and a second end that defines a tab, wherein the pin slot engages a pin portion of the second trigger lever such that as the second trigger lever rotates about a second trigger lever pivot point the pin portion moves within the pin slot to apply a rotational motion to the second trigger lever.

5. The medical instrument according to claim 4, wherein the second trigger lever comprises a second tab to engage an aperture to mechanically couple the second trigger lever to a proximal end of the sheath, wherein as the trigger lever rotates about the trigger pivot point the second trigger lever rotates about the second trigger lever pivot point to apply a linear motion to an inner sheath in the distal direction.

6. The medical instrument according to claim 5, comprising a second torsion spring to engage the second trigger lever at a notch formed in the second trigger lever, wherein a second torsion spring torque balances a force applied to the second trigger lever through the control lever about the trigger pivot point.

7. The medical instrument according to claim 1, wherein the activation button actuates a switch to enable electrical actuation of the RF generation circuit without unlocking the cutting blade.

8. The medical instrument according to claim 1, comprising a tang to prevent the activation button from being removed by pulling distally on tang.

9. A method of operating a medical instrument, comprising a housing;

at least one electrical contact;

a radio frequency (RF) generation circuit coupled to and operated by a battery and operable to generate an RF drive signal and to provide the RF drive signal to the at least one electrical contact;

an activation button coupled to an activation button lever supported by the housing, the activation button controls the activation of the RF generation circuit to apply the RF drive signal to the at least one electrical contact, the activation button lever comprising a top surface, the activation button lever rotatable about an activation button pivot point;

a cutting blade operably coupled to a sheath; and

a control lever supported by the housing and pivotally coupled to a trigger lever comprising a projection to engage the top surface of the activation button lever, the control lever is operable to control the actuation of the cutting blade by actuating the sheath in a distal direction when the control lever is rotatably moved proximally about a trigger pivot point, the method comprising;

locking out the cutting blade until the activation button is fully engaged to activate the RF generation circuit.

10. The method according to claim 9, comprising:

fully engaging the activation button; and

squeezing the control lever to actuate the cutting blade.