Surgical handpiece with self-sealing switch assembly

• US 6,461,352 B2
• Filed: 03/05/2001
• Issued: 10/08/2002
• Est. Priority Date: 05/11/1999
• Status: Expired due to Fees

• Current Assignee: Stryker Corporation
• Original Assignee: Stryker Corporation
• Inventors: Prakash, Mani, Morgan, Roy, Saravia, Heber, Voges, Jens
• Primary Examiner(s): Kearney, Rosiland S.
• Application Number:
  US09/799,817
• Publication Number:
  US 20010049524A1
• Time in Patent Office: 582 Days
• Field of Search: 606/27, 606/29, 606/30, 606/32, 606/34, 606/37, 606/39, 606/40, 606/41, 606/42, 606/45, 606/46, 606/47, 606/48, 606/49, 606/50, 607/96, 607/98, 607/99, 607/100, 607/101, 607/104, 607/105
• US Class Current: 606/34
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/148 having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy
• CPC Class Codes: A61B 2017/00482 with a code
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61B 2218/007 Aspiration
• CPC Class Codes: H01H 2300/014 Application surgical instrument

Abstract

An bipolar electrosurgical tool (10) for cauterizing or ablating tissue. The tool has a nose cone (12) which serves as a handle. A conductive shaft (14) extends from the nose cone. A tip assembly (18) with an active electrode (20) is mounted to the shaft. A circuit board (78) is mounted in the nose cone. Conductive traces that forming contact pads (96, 102) are formed on the circuit board. A web (108) formed from a single piece of elastomeric material is seated over the opening in which the printed circuit board is mounted to seal the opening shut. Integrally formed with the web are buttons (116, 118) that are in registration over the contact pads. The buttons can be depressed downwardly towards the contact pads. When a button is so depressed, a conductive landing pad (120) integral with the button closes the connection between the traces that form the contact pad. Thus, the tool of this invention is provided with switches. The circuit board also has two conductive traces (92, 104a) that run in parallel. If there is a leak into the nose cone, a connection is established across these traces and shorts out a resistor (105). The shorting out of this resistor provides a control console (22) with an indication that there is a leak. The electrode is formed from a single piece of tantalum. The electrode has a head formed with a hole (172) trough which fluid flows. The electrode is seated in a sleeve (136b) provided with a through bore (177) in registration with the electrode hole.

Claims

1. A powered surgical handpiece, said handpiece comprising:

a housing, said housing have an outer surface and an opening that is formed in the outer surface that defines a wiring space in said housing, the wiring space being defined by a perimeter section of the outer surface of said housing;

a surgical implement that extends from said housing, said surgical implement being selectively actuated based on application of a variable control signal;

a circuit board fixedly mounted in the wiring space of said housing, said circuit board having an outwardly directed surface and a plurality of conductive traces formed on the outwardly directed surface so as to define a contact pad;

a flange fixedly disposed in the wiring space of said housing, said flange positioned to circumferentially surround said circuit board and positioned to be spaced inwardly of the perimeter section of the outer surface of said housing; and

a web formed of elastomeric material that is mounted to said housing, said web having;

a base positioned in the opening of said housing, said base having an outer edge;

a lip that extends circumferentially around and away form the outer edge of said base, said lip positioned to be located between the perimeter section of the outer surface of said housing and said flange, said lip being dimensioned to be compression fitted between the outer surface of said housing and said flange;

a button formed integrally with said base so that said button flexes relative to surrounding portions of said base, wherein said button is positioned to be located over said contact pad and is constructed so that, upon depression of said button, said button abuts said contact pad; and

a landing pad located on an undersurface of said button that is directed towards said contact pad and is positioned, so that, when said button abuts said contact pad, said landing pad abuts said contact pad, said landing pad having a layer of conductive material thereon, so that, when said landing pad abuts said contact pad, the conductive material establishes a conductive path between said conductive traces.

2. The powered surgical handpiece of claim 1, wherein said web is further formed to have a slit in said lip that extends inwardly from an outer surface of said web.

3. The powered surgical handpiece of claim 2, wherein said web is formed so that the slit extends circumferentially around said lip.

4. The powered surgical handpiece of claim 1, wherein said web is formed so that said lip has an inner surface that is directed towards said flange and the inner surface of said lip is formed to have a plurality of spaced apart ribs, wherein said ribs abut said flange.

5. The powered surgical handpiece of claim 1, wherein:

said conductive traces are arranged on said circuit board to form a plurality of contact pads; and

said web is formed to have a plurality of buttons, each said button being located over a separate one of said contact pads and each said button is provided with a separate said landing pad.

6. The powered surgical handpiece of claim 1, wherein said web is formed from silicone rubber.

7. The powered surgical handpiece of claim 1, wherein said landing pad is formed from graphite.

8. The powered surgical handpiece of claim 1, wherein said surgical implement is an electrosurgical probe having a tip from which an electric current is discharged.

9. The powered surgical handpiece of claim 1, further including:

a first leak detect trace disposed on said circuit board;

a second leak detect trace disposed on said circuit board, said second leak detect trace having a branch that extends parallel to said first leak detect trace;

a resistor mounted to said circuit board, said resistor extending between said first leak detect trace and said second leak detect trace; and

a leak detect circuit external to said housing, said leak detect circuit being connected to said first leak detect trace and to said second leak detect trace, said leak detect circuit including;

a power supply for supplying a voltage to said leak detect traces to cause a voltage to develop across said leak detect traces; and

a voltage measuring circuit for measuring the voltage across said leak detect traces.

10. The powered surgical handpiece of claim 9, wherein:

said first leak detect trace is one of said traces that define said contact pad and said first leak detect trace is arranged on said circuit board so as to define at least a portion of the outer perimeter of said contact pad and the branch of said second leak detect trace is located adjacent the portion of said first leak detect trace that defines the outer perimeter of said contact pad.

11. A powered surgical handpiece, said handpiecce comprising:

a handle, said handle having an outer surface that has an opening that defines a wiring space in said handle;

an electrically actuated surgical implement that extends from said handle;

a wall integral with said handle and located in the wiring space, said wall being spaced inwardly from edge portions of said outer surface of said handle that define the opening and being formed to define a seating space within said wiring space that is circumferentially enclosed by said wall and said wall has an outer surface;

a circuit board disposed inside the seating space, said circuit board having a contact pad that is formed by two spaced apart conductive traces;

a single-piece web formed of elastomeric material mounted to said handle, said web having;

a circumferentially extending flange that is disposed in the wiring space in an interstitial space between the edge portions of the outer surface of said handle and the outer surface of said wall, and said flange is dimensioned to be compression secured between the outer surface of said handle and said wall; and

a base that extends from said flange over the opening in said handle, said base being formed to define a button that is disposed over said contact pad and said base is formed so that said button can be inwardly flexed to abut said contact pad; and

a landing pad that includes a conductive layer that is secured to a surface of said button that abuts said contact pad.

12. The powered surgical handpiece of claim 11, wherein said web is further formed to have a slit in said flange that extends inwardly from an outer surface of said flange.

13. The powered surgical handpiece of claim 12, wherein said web is formed so that the slit extends circumferentially around said flange.

14. The powered surgical handpiece of claim 11, wherein said web is formed so that said flange has an inner surface that is directed towards said wall and the inner surface of said flange is formed to have a plurality of spaced apart ribs, wherein said ribs abut said wall.

15. The powered surgical handpiece of claim 11, wherein:

said conductive traces are arranged on said circuit board to form a plurality of contact pads; and

said web is formed to have a plurality of buttons, each said button being located over a separate one of said contact pads and each said button is provided with a separate said landing pad.

16. The powered surgical handpiece of claim 11, wherein said web is formed from silicone rubber.

17. The powered surgical handpiece of claim 11, wherein said landing pad is formed from graphite.

18. The powered surgical handpiece of claim 11, wherein said surgical implement is an electrosurgical probe having a tip from which an electric current is discharged.

19. The powered surgical handpiece of claim 11, further including:

a first leak detect trace disposed on said circuit board;

a second leak detect trace disposed on said circuit board, said second leak detect trace having a branch that that extends parallel to said first leak detect trace;

a resistor mounted to said circuit board, said resistor extending between said first leak detect trace and said second leak detect trace; and

a leak detect circuit external to said housing, said leak detect circuit being connected to said first leak detect trace and to said second leak detect trace, said leak detect circuit including;

a power supply for supplying a voltage to said leak detect traces to cause a voltage to develop across said leak detect traces; and

a voltage measuring circuit for measuring the voltage across said leak detect traces.

20. The powered surgical handpiece of claim 19, wherein:

said first leak detect trace is one of said traces that define said contact pad and said first leak detect trace is arranged on said circuit board so as to define at least a portion of the outer perimeter of said contact pad and the branch of said second leak detect trace is located adjacent the portion of said first leak detect trace that defines the outer perimeter of said contact pad.

21. A powered surgical handpiece, said handpiece comprising:

a housing, said housing have an outer surface and an opening that is formed in the outer surface that defines a wiring space in said housing, the wiring space being defined by a perimeter section of the outer surface of said housing;

a surgical implement that extends from said housing, said surgical implement being selectively actuated based on application of a variable control signal;

a circuit board fixedly mounted in the wiring space of said housing, said circuit board having an outwardly directed surface and a plurality of conductive traces formed on the outwardly directed surface so as to define a contact pad;

a flange fixedly positioned in the wiring space of said housing, said flange positioned to circumferentially surround said circuit board and positioned to be spaced inwardly of the perimeter section of the outer surface of said housing; and

a web formed of elastomeric material that is mounted to said housing, said web having;

a base positioned in the opening of said housing, said web having an outer edge;

a lip that extends circumferentially around and away form the outer edge of said base, said lip formed to have a slit that extends inwardly from an outer surface of said web and that extends circumferentially around said base and an inner surface that is formed to have a plurality of spaced-apart ribs and said lip is positioned to be located between the perimeter section of the outer surface of said housing and said flange and is dimensioned to be compression fitted between the outer surface of said housing and said flange so that said ribs abut said flange;

a button formed integrally with said base so that said button flexes relative to surrounding portions of said base, wherein said button is positioned to be located over said contact pad and is constructed so that, upon depression of said button, said button abuts said contact pad; and

a landing pad that includes a layer of conductive material attached to a surface of said button that is directed towards said contact pad, so that when said button abuts said contact pad, said landing pad abuts said conductive traces that form said contact pad and the conductive material establishes a conductive path between said conductive traces.

22. The powered surgical handpiece of claim 21, wherein:

said conductive traces are arranged on said circuit board to form a plurality of contact pads; and

said web is formed to have a plurality of buttons, each said button being located over a separate one of said contact pads and each said button is provided with a separate said landing pad.

23. The powered surgical handpiece of claim 21, wherein said web is formed from silicone rubber.

24. The powered surgical handpiece of claim 21, wherein said landing pad is formed from graphite.

25. The powered surgical handpiece of claim 21, wherein said surgical implement is an electrosurgical probe having a tip from which an electric current is discharged.

26. The powered surgical handpiece of claim 21, further including:

a first leak detect trace disposed on said circuit board;

a second leak detect trace disposed on said circuit board, said second leak detect circuit trace having a branch that extends parallel to said first leak detect trace;

a resistor mounted to said circuit board, said resistor extending between said first leak detect trace and said second leak detect trace; and

a leak detect circuit external to said housing, said leak detect circuit being connected to said first leak detect trace and to said second leak detect trace, said leak detect circuit including;

a power supply for supplying a voltage to said leak detect traces to cause a voltage to develop across said leak detect traces; and

a voltage measuring circuit for measuring the voltage across said leak detect traces.

27. The powered surgical handpiece of claim 25, wherein:

said first leak detect trace is one of said traces that define said contact pad and said first leak detect trace is arranged on said circuit board so as to define at least a portion of the outer perimeter of said contact pad and the branch of said second leak detect trace is located adjacent the portion of said first leak detect trace that defines the outer perimeter of said contact pad.