Compact Hand Held Switching Device With Insertable Switching Means

Abstract

A surgical tool of the type in which cutting or cauterizing current is selectively introduced to a blade by means of a finger-operated switch actuating member, the tool comprised of an outer case and a correspondingly structured removable insert carrying the switching mechanism, the switch actuating arm between the switch actuating member and the switch mounted to reciprocate in a plane normal to the axis about which the switch actuating member oscillates to provide a compact pencil-type device, the combination case and insert being adaptable to provide switching means for applications other than surgical tools. The switches have threaded extensions which are inserted through trunnions in the casing and held there by clamping units.

Description

BACKGROUND OF THE INVENTION

Finger-actuated slide-type electrical switches for actuating a single circuit, or for selectively actuating a plurality of circuits, are well known and such are illustrated by U.S. Pat. No. 3,217,112. This patent discloses a rocker-type switch for selectively actuating a plurality of circuits, the actuating element between the rocker and the movable switch contact being perpendicular to the longitudinal axis of the case. This switch has limited application and its construction results in a rather bulky device not susceptible for use in connection with a longitudinal pencil-shaped surgical tool which can be easily held in one hand of the physician for operation.

Finger-actuated surgical devices for the dual purpose of cutting and cauterizing tissue by the selective application of high-frequency varyingly damped current of the selected type and power are also well known as exemplified by U.S. Pat. No. 1,813,902, and related U.S. Pat. Nos. 2,611,635; 3,058,470; 3,089,496; and 3,100,489. Surgical tools of somewhat pencillike dimensions having a switch therein are also well known, as exemplified by U.S. Pat. Nos. 1,684,143 and 3,234,356. The advantages of a surgical tool of this type having a finger-actuated switch over surgical tools having a foot pedal-operated switch or one operated by an assistant, are amply set forth in these patents and need no further amplification here. The finger-actuated surgical tools of the prior art are somewhat bulky in construction, do not lend themselves to facile sterilization procedures and techniques, and cannot be manufactured by relatively inexpensive plastic molding techniques.

Accordingly, it is a principle object of this invention to provide an electrical slide switch particularly adapted for use in surgical tools, which can be incorporated in a pencil-type case for ease in handling, and which is readily adaptable for sterilization with standard sterilization procedures, and which can be readily and inexpensively manufactured by conventional plastic molding techniques.

SUMMARY OF THE INVENTION

A pencil-type electrical switching device comprising a plastic tubular housing having a rocker-type finger-actuated switching device mounted in a slot therein to oscillate around an axis perpendicular to the longitudinal axis of the housing to reciprocally move a switching arm perpendicular thereto constructed to selectively actuate a plurality of switches, an application being in combination with a cutting and coagulating surgical blade adapted to be selectively placed in electrical contact, through control circuits controlled by the switching device, with an output source of a plurality of types of electric current of variable power. A preferred embodiment comprises the use with the housing incorporating the rocker-type switching element, of an insert assembly mounting the switches and having a slot cooperating with the slot in the housing to permit actuation of the rocker-type actuating element, and a slot in its bottom in which the actuating arm reciprocates.

The invention is best understood by reference to the accompanying drawing in which:

FIG. 1 is a longitudinal partial cross-sectional view of the switching device used with the surgical tool and showing the insert assembly in place;

FIG. 1A is a diagrammatic showing of the feeder devices for the switching device of FIG. 1;

FIG. 2 is a cross-sectional view of the insert taken on the line 2--2 of FIG. 1;

FIG. 3 is a cross-sectional view taken on line 3--3 of FIG. 1;

FIG. 4 is a cross-sectional view taken on line 4--4 of FIG. 1; and

FIG. 5 is a cross-sectional view taken on line 5--5 of FIG. 1.

Referring to the drawing, the switching device comprises an outer housing 10, preferably of plastic, having a longitudinal slot 12 therein in which is mounted finger-actuated, rocker-type actuating element 14 on anchor pin 16 for oscillation in a plane perpendicular to the longitudinal axis of the housing 10. A cap 18 having central channel 20 provided with seat 22 and leading into expanded recess 23 is threadedly attached to housing 10 by means of female threads 24 in the internal surface of the front end of housing 10 and mating male threads 26 on the external surface of the rear end of cap 18. The housing 10 may be provided with an internal bushing 28 having a channel 30 therein for the passage of a cable sheath 32 which may enclose wiring for a plurality of circuits.

In the preferred embodiment, the internal components of the switching device are mounted in a cylindrical insert 34 having a radius of curvature substantially the same as that of the housing 10 to provide for a good fit inside the housing. The insert 34 comprises a frame 36 having a head 38 and a semicircular portion 39 made by cutting away a portion of the cylindrical frame 36 to leave head 38. The head 38 is provided with a slot 40 extending therethrough and correspondingly positioned as respects slot 12 to seat actuating element 14 and permit its oscillation therein. Head 38 is provided with a radial slot (FIG. 2) corresponding positionwise with the holes in housing 10 in which anchor pin 16 is seated so that when the insert 34 is in place, it can be locked in the housing by means of anchor pin 16 extending through the slot in the head 38 and the correspondingly positioned holes in outer housing 10.

Rocker element 14 is constructed so that its bottom section 44 terminates in an apex which is longitudinally split (FIG. 2) and is provided with a radially extending hole 46 which acts as a trunnion for seating a trunnion pin therein.

Electrical two-place switches 50 and 52 are mounted in frame 36 in a manner to be described. The switches are of standard type known as "Butt Contact Push Button Switches" manufactured and commercially sold by the Grey Hill Company. The prongs 54 and 56 connect with stationary contacts inside the switch housings having a gap therebetween. Insulating switch buttons 58 and 60, reciprocably mounted in the switch housings, are connected to a movable contact plate for bridging the gap between the internal contacts for prongs 54 and 56 and are spring biased into their outward or out-of-contact position, in accordance with well-known conventional switch constructions. Each of the switches is provided with hollow threaded extensions 62 and 64 in which buttons 58 and 60 reciprocate.

Vertically slotted walls or trunnions 66 and 68 are integrally molded inside the insert 34 and radial grooves 70 and 72 are machined adjacent the bottom of these trunnions as shown. In mounting the switches 50 and 52 in the insert 34, the threaded extensions 62 and 64 are seated in the trunnions 66 and 68, respectively, with the trunnions between the switches and corresponding clamping nuts 74 and 76 on threaded extensions 62 and 64, and the nuts screwed tightly against the trunnions to hold the switches securely in place.

For actuating the buttons 58 and 60 of the switches, switch actuating arm 78 is mounted inside the insert 34 and housing 10 to reciprocate in a plane perpendicular to the plane of oscillation of the rocker element 14. Switch actuating arm 78 has trunnion pin 80 axially mounted at one end and rotatably seated in trunnion 46. The other end of actuating arm 78 terminates in perpendicular actuating contact end 82 which rests between insulating buttons 58 and 60 to alternately actuate same as the rocker element 14 oscillates. It will be seen that the actuating end 82 has three positions, that is, the left position in which switch 50 is actuated, the right position in which switch 52 is actuated and the neutral position as shown in which neither switch is actuated. This latter position corresponding to the null position of rocker element 14 is shown in FIG. 1. Insert 34 is provided with a longitudinal slot 84 (FIG. 2) in its bottom in which actuating arm 78 reciprocates. The actuating arm will, of course, be held in place by the internal surface of outer housing 10 with the insert in place.

In operation of the switching function, one side of actuating element 14 is depressed, depending upon which switch is to be actuated, and movement of actuating arm 78 will depress one of the insulating buttons 58 or 60 of the desired switch to move the movable contact element connected to it in contact with the two internal contacts connected to prongs 54 and 56 to bridge the gap between the two contacts and cut in the circuit. The two switches 50 and 52 can, of course, be arranged to actuate any type circuit desired for the required application by means of the circuit connections contained in cable sheath 32. The application of the switching device to a surgical tool will now be described.

A conducting metal collet 86 is mounted in the front end of housing 10 by means of screw threads on end 88 fastening in mating threads in head 38, the threaded end 88 being provided with an abutment flange 90 which seats against the forward end of head 38. The collet 86 is provided with three longitudinal intersecting slots 92 into which is inserted with a close fit tongues 94 of a surgical cutting and coagulating blade 96. The blade, tongues, and threaded end 88 are all constructed of conducting material. Threaded end 88 is adapted to be selectively placed in electrical contact with high frequency current of varying type and power by means of control circuits actuated by switches 50 and 52.

A high frequency current source providing an output of varying types of current and varying power is shown schematically at 98 connected to control circuits of standard type represented schematically at 100 which are connected to the two switches so that selective control of the control circuits to provide the preselected type of high-frequency current with the required power can be exercised with finger tip control by the surgeon holding the instrument in his hand for selectively cutting tissue or coagulating blood vessels, etc., with blade 96. A longitudinal groove 102 (FIG. 5) is provided between head 38 and case 10 for receiving wiring to connect threaded end 88 with switches 50 and 52.

Claims

What is claimed is:

1. An electrical switch device comprising:

a. an elongated tube having a cylindrical bore therein forming a tubular housing and having a slot in the wall thereof intermediate its ends, said housing including a pair of juxtaposed internal trunnions formed therein;

b. a pair of juxtaposed electrical switches mounted in said housing, each of said switches having a threaded extension formed on one end thereof, each of said switches having a pair of stationary electrical contacts for bridging the gap therebetween, each of said movable contacts being normally biased out of contact with its corresponding pair of stationary electrical contacts;

c. a pair of clamping nuts for securing said electrical switches within said housing, each of said switches being mounted in said housing with its threaded extension in a corresponding trunnion, each trunnion being disposed between its corresponding switch and clamping nut;

d. a rocker-type switch actuator pivotally mounted in said slot to rotate about an axis normal to the longitudinal axis of the housing;

e. said actuator having a finger engaging portion on one side of its pivotal mounting disposed outside of the housing adapted to be engaged by a finger of an operator for selectively rotating same in opposite directions;

f. said actuator having a lever portion at the opposite side of its pivotal mounting disposed within the housing; and

g. an actuating arm within the housing extending in the longitudinal direction thereof having one end pivotally connected to said lever portion, the other end of said actuating arm extending laterally from said arm and being disposed between the movable electrical contacts of said switches to alternately move a movable electrical contact to bridge its respective pair of stationary contacts.

2. The electrical switching device of claim 1 in which said switches include an insulating button actuating said movable contact being reciprocable in said threaded extension and biased to its outward position.

3. The electrical switching device of claim 1 including an insert assembly for removably inserting in said housing, comprising: a cylindrical body having a radius of curvature substantially the same as that of said housing, said switches mounted in said body, a first longitudinal slot in said body corresponding to the slot in said housing and receiving said switch actuator, and a second longitudinal slot in the bottom of said body for receiving said actuating arm for reciprocation therein.

4. The electrical switching device of claim 3 in which said switch actuator has a trunnion in its lower end and said actuating arm has a trunnion pin on said one end seating in said trunnion.

5. The electrical switching device of claim 1 including an insert assembly for removably inserting in said housing, comprising: a cylindrical body having a radius of curvature substantially the same as that of said housing and having a head portion and a semicircular portion, said trunnions and said switches being mounted in said semicircular portion, a first longitudinal slot in said head portion corresponding to the slot in said housing and receiving said switch actuator, and a second longitudinal slot in the bottom of said body for receiving said actuating arm for reciprocation therein.