WO1997045062A1

WO1997045062A1 - Clamp for electrosurgical dispersive electrode

Info

Publication number: WO1997045062A1
Application number: PCT/US1996/014769
Authority: WO
Inventors: Craig D. Oster; David C. Bryam
Original assignee: Minnesota Mining And Manufacturing Company
Priority date: 1996-05-30
Filing date: 1996-09-16
Publication date: 1997-12-04
Also published as: AU7159696A

Abstract

A clamp (10) for a dispersive electrode is disclosed. The clamp comprises (a) a housing (14) having an exterior surface (15), an interior surface (25) being formed within the housing for receiving projecting tabs of the electrode, and a slot (20) in the housing disposed between the exterior surface and the interior surface; and (b) sliding means (22) for releasably engaging the tabs at the interior surface, comprising a locking rib on a slide and a locking catch on the interior surface of the housing.

Description

CLAMP FOR ELECTROSURGICAL DISPERSIVE ELECTRODE

Field of Invention This invention relates to clamps for dispersive electrodes.

Background of Invention

Biomedical electrodes are used in a variety of applications and are configured to operate according to the size, type, and direction of current flowing into or out of a body of a patient.

Dispersive electrodes are used in electrosurgery. In modern surgical practice there are many times when electrosurgery is more preferable than the use of the traditional scalpel. In electrosurgery, cutting is performed by an intense electrical current passing through a cutting electrode. The surgeon directs this current to exactly where cutting is required by wielding the cutting electrode, which because of its cylindrical shape and the way it is held in the hand is commonly called an "electrosurgical pencil". By activating controls which change the characteristics of the electrical current being sent to the pencil by an electrosurgical generator, the surgeon can use the pencil either to cut or to coagulate areas of bleeding. This makes electrosurgery particularly convenient when surgery requiring extra control of blood loss is being performed. Because of concerns to minimize the transmissions of blood-borne illnesses between health care patients and health care providers, in both directions, electrosurgery is becoming increasingly important.

In electrosurgery, as in all situations where electrical current is flowing, a complete circuit must be provided to and from the current source. In this case, the current that enters the body at the pencil must leave it in another place and return to the generator. It will readily be appreciated that when current enough to deliberately cut is brought to the body of a patient in one place, great care must be taken that unintentional damage is not also done to the patient at the location where that current is leaving the body. The task of collecting the return current safely is performed by a dispersive electrode. A dispersive electrode performs this task by providing a large surface area through which the current can pass; the same current which was at cutting intensity when focused at the small surface area at the tip of the pencil is relatively harmless, with the goal of being painless to the patient, when spread out over the large surface area of the dispersive electrode.

Between the dispersive electrode and the electrosurgical generator, the typical manner to complete the circuit is to electrically connect the end of the dispersive electrode to a clamp connected to an electrical wire ending in a plug compatible with the electrosurgical generator. Any tendency toward disconnection of the clamp from the dispersive electrode is critical to maintenance of the electrical circuit.

Some clamps are known to those skilled in the art. Two examples of clamps are represented by U.S. Pat. Nos. 4,061,408 (Bast et al.) and 4,952, 177 (Drake et al ). Commercially available clamps related to such patents are available from 3M Health Care of Minnesota Mining and Manufacturing Company of St. Paul, MN.

Smaller size clamps, known as clips, are used for smaller biomedical electrodes used to receive electrical signals from a patient's body. Examples of such clips are represented by U.S. Pat. Nos. 4,555,155 (Drake et al ); 4,700,997 (Strand et al.); 4,842,558 (Strand et al.); 5,407,368 (Strand); and 5,454,739 (Strand). While clamps and clips serve similar purposes to complete an electrical connection, the dispersive electrode used with a clamp differs from an electrocardiographic electrode used with a clip, in that the dispersive electrode can have two different electrically conductive surfaces for Contact Quality Monitoring ("CQM") circuitry that tests continued adequate electrical connection of the electrode with the clamp to avoid burning skin of the patient.

Summary of Invention

The present invention provides a clamp that has different features from that found in prior clamps or clips. The clamp for an electrosurgical electrode (a) a housing having an exterior surface, an interior surface being formed within the housing for receiving projecting tabs of the electrode, and a slot in the housing disposed between the exterior surface and the interior surface; and (b) sliding means for releasably engaging the tabs at the interior surface, comprising a locking rib on a slide and a locking catch on the interior surface of the housing. A feature of the present invention is an ergonomic sliding action to positively contain tabs of an electrode within the clamp.

Embodiments of the invention follow the brief description of the drawings.

Brief Description of Drawings

FIG. 1 is a top plan view of a clamp of the present invention. FIG. 2 is a cross-sectional view of the clamp as seen on Section lines 2-2 in FIG. 1.

Embodiments of Invention

Clamp 10 is connected to a cable 12 having a strain relief 13 engaging a clamp housing 14 having an exterior surface 15. The cable 12 is connected to the electrosurgical generator (not shown) which may require an electrical adaptor for proper electrical connection. The housing 14 is divided into a first cover 16 and a second cover

18. The housing 14 is configured to have a tabs receiving slot 20 at a point on its exterior surface 15 of joinder between first cover 16 and second cover 18 to allow insertion of tabs of a dispersive electrode into the housing 14.

A slide 22 that moves toward slot 20 resides in upper slot 24 on the exterior surface 15 of first cover 16. The first cover 16 and the second cover 18 are secured by latches received in notches in the housing 14 on the exterior surface 15 not adjacent to the tabs receiving slot 20.

The slide 22 is composed of a ribbed surface 30, a contact rib 32, and a locking rib 34 opposing rib 32 on a portion of slide 22 proximal to slot 20. On the interior surface 25 of housing 14, one of two receiving electrical contact strips 38 (the other strip being in parallel relation in the portion of clamp 10 not sectioned) is shown in its restrained position. In this embodiment, strip 38 is generally U-shaped flat spring configured to receive a tab of the electrode.

Also on interior surface 25 of housing 14 are a sliding ramp 40 upon which slide 22 moves at approximately an angle of -15°, and a locking catch 42 for releasably receiving locking rib 34 and retaining the position of slide 22 relative to housing 14 to lock strip 38 around a tab of the electrode inserted into slot 20.

Wires 44 from lead cable 12 and strain relief 13 pass through second cover 18 and are secured by soldering ot other elecrtrically conductive securing means to the respective separated electrical contact strips.

When tabs of the electrode are inserted into clamp 10 through slot 20, tabs must be releasably engaged to maintain continuous electrical connection with the separated electrical contact strips within the housing. The means for releasably engaging the tabs are composed of slide 22, sliding ramp 40, and the combination of locking rib 34 and locking catch 42.

While embodiments of the invention have been disclosed, the claims of the invention follow.

Claims

What is claimed is:

1. A clamp 10 for an electrosurgical electrode, comprising:

(a) a housing 14 having an exterior surface 15, an interior surface 25 being formed within the housing for receiving projecting tabs of the electrode, and a slot

20 in the housing disposed between the exterior surface and the interior surface; and

(b) sliding means 22 for releasably engaging the tabs at the interior surface, comprising a locking rib 34 on a slide and a locking catch 42 on the interior surface of the housing.

2. The clamp according to Claim 1, wherein the housing is divided into a first cover 16 and a second cover 18.

3. The clamp according to Claim 2, wherein the housing 14 is configured to have the slot 20 at a point on the exterior surface 15 of joinder between the first cover 16 and the second cover 18.

4. The clamp according to any of Claims 1-3, wherein the sliding means comprises a slide 22 that moves toward the slot 20 and resides in an upper slot 24 on the exterior surface of the first cover 16.

5. The clamp according to Claim 4, wherein the first cover 16 and the second cover 18 are secured by latches received in notches in the housing on the exterior surface not adjacent to the slot.

6. The clamp according to Claim 4, wherein the slide 22 comprises a ribbed surface 30 and a contact rib 32, and wherein the locking rib 34 opposes contact rib 32 on a portion of the slide 22 proximal to the slot 20.

7. The clamp according to any of Claims 1-6, further comprising two receiving electrical contact strips 38 on the interior surface of the housing.

8. The clamp according to Claim 6, further comprising a sliding ramp 40 upon which the slide moves at approximately an angle of -15° and wherein the locking catch 42 releasably receives the locking rib 34 and retains the position of slide 22 relative to the housing 14.