Medical instrument

1,978,495

Oct. 30, 1934.

A. LANDAU

MEDICAL INSTRUMENT

Filed Nov. 2, 1929

<img file="US1978495A_D0001.tif" />

Patented Oct. 30, 1934

1,978,495

UNITED STATES PATENT OFFICE

1,978,495

MEDICAL INSTRUMENT

Arnold Landau, Berlin-Friedenau, Germany, assignor to the firm, Elektrieitatsgesellsehaft “Sanitas” m. b. IL, Berlin, Germany

Application November 2,1929, Serial No. 404,332 In Germany October 8, 1927

Claims. (Cl. 174—89)

My invention relates to medical instruments and more particularly to instruments designed for the application of high frequency currents.

It is an object of my invention to provide 5 means whereby sparking at the body of the patient is eliminated. To this end I so design my instrument that the circuit for the electric current is completed only after contact has been established between the instrument and the body 1® of the patient.

It is another object of my invention to avoid electric reactions on the body of the operator. To this end I provide a separate circuit in connection with a relay, and I connect the circuit IS of the relay with the handle of the instrument so that in case of any leakage only the comparatively weak; current of the relay circuit and not the strong current of the line circuit; will flow through the body of the operator.

; 20 In the drawing affixed to this specification and forming part thereof various instruments embodying my invention are illustrated diagrammatically by way of example.

In the drawing &lt;

Fig. 1 is a partly sectional plan view of an instrument of the tonsillotome or adenotome type, without a relay,

Fig. 2 is a diagram of connections showing a relay with a battery circuit,

Fig. 3 is a diagram showing a relay the circuit of which is shunted from the line wires,

Fig. 4 is a diagram showing a mechanically operated relay,

Fig. 5 is a diagram showing an instrument 35 having a relay in a battery circuit as in Fig. 2, but with a modified arrangement of the blade, and

Fig. 6 is a diagram showing an instrument in which the, circuit of the relay is completed 4o through the body of the patient.

Referring now to the drawing and first to Fig. 1, 1 is a casing of insulating material which at its front end is provided with a loop or guide 2. The guide is grooved for the reception of the 45 blade 3, which is one of the electrodes. 4 is a handle with an eye 7 which handle is fitted to slide in the casing 1, 5 is the opposite electrode which is seated on the threaded end 8 of the handle 4, 13 is an insulated or insulating bush 50 on the electrode which serves as an abutment for a spring 6, 14 is the mating bush: at the other end of the spring 6, 9 is a slide secured to the inner end of the blade or electrode 3, 10 is a conductor in the slide 9, 15 is a conductor which 55 is connected with a contact spring 12, the contact spring sliding on the electrode 5 with its end 16, 17 is a contact spring at the end of the electrode 5 which together with a reduced projection 18 at the end of the electrode, makes a sort of clamp or seat for the pointed end of the co conductor 10, and 11 is a shoulder at the inner end of the slide 7 which, when the circuit is closed at 10, 17, 18, is engaged by the end of the spring 16, breaks the circuit and holds the slide in position. Another conductor, not shown, 03 is provided for carrying away the current from the electrode 3· The handle 4 is of insulating material as shown but obviously might be of conducting material, and insulated from the electrode 5. 73

In operation, the instrument is placed on a part of the patient’s body, for instance a tonsil, and then pressure is applied on the handle 7 to push the electrode 5 toward the point of the conductor 10. It will be understood that the blade 3 is advanced 75 freely Until it contacts with the tonsil and thereupon an increasing pressure reaction is exerted on the spring 6 but still the circuit is not closed so that the electrode 3 is applied without sparking. Only after the spring 6 has been compressed go to such an extent that the circuit is closed at 17 and 18, current flows in the electrode, while the blade 3 still advances for. separating the tonsil. When the blade has been advanced so far that the end 16 of spring 12 engages behind the shoul- 85 der 11 of the slide 4 the circuit is broken and remains in this condition until the slide:is released by turning it through about 90 degrees. In this manner, sparking at the body of the patient when removing the instrument is also eliminated as the go slide 4 will only be released after the instrument has been retracted from the body of the patient.

In the. operation of the instrument as described, it is seen that the spring 6 and the electric switch, comprising the contact, elements 17, 95 18 and the pointed end of the conductor 10, act as means for temporarily preventing flow of diathermic current when the tool or blade 3 is in its initial position prior to an operative stroke and for permitting flow of said current through a pa- ¹⁰⁰tient’s body during such operative stroke; said means being operated by and substantially simultaneously with contact of said tool with said patient’s body. The spring 12 cooperating with shoulder 11 acts as means for breaking the'diathermic current at the conclusion of an operative stroke without independent manipulation; that is breaking of the current occurs as an incident of the operating stroke.

ί,978,49£>

In this, the simplest form of the instrument, sparking at the blade 3 is avoided at the beginning and at the end of the operation but still there is the risk of injury to the operator through leakage from the electrode 5. This is avoided in the several arrangements the diagrams of which are illustrated in Figs. 2-6.

Referring first to Fig. 2, the electrodes 3 and 5, with the spring 6 between them, are indicated only diagrammatically. The body of the patient, a tonsil as assumed in the present instance, is in-, dicated by the sectioned area 19, 20 are the line wires of a system, 21 is a diathermic apparatus of any suitable kind, 22 and 23 are wires extending from the apparatus to the blade 3 and the tonsil 19, respectively, 24 is a battery, 26 is a relay in the diathermic apparatus, and 27,-28 are the wires of the relay-and-battery circuit.

It will be understood that when the electrodes 3 and 5 get into contact, as described with reference to Fig. 1, the circuit 27, 28 of the relay 26 is closed and the relay cuts in the circuit 22, 23 through the blade 3 and the body of the patient. Here, sparking is also avoided because the circuit of the relay 26, and consequently the circuit 22, 23 can only be closed after the electrode 3 has come into contact with the body of the patient but, in addition, the operator is protected against the strong current from the system £0.

Referring now to Fig. 3, the arrangement is the same as described with reference to Fig. 2, with the exception that the circuit of the relay 26 is constituted by a shunt 29, 30 from the system 20.

Referring now to Fig. 4, the relay 26 is here operated mechanically through the medium of a flexible bar 31 which is attached to the electrode 5 and is fitted to. slide in a flexible tube 32 which is secured at one end to the electrode 3.

Referring now to Fig. 5, this illustrates an apparatus in which the electrode 5 is not pushed but pulled as indicated by the arrow. The spring 6 is inserted between an extension 25 of the electrode 5, and an extension 33 at the end of the blade or electrode 3, which in the present instance is designed like the loop 2, Fig. 1, with an opening 34. The blade 3 is placed on the tonsil 19 so as to engage it with the closed end of the loop 34, and a pull is exerted at the end of the electrode 5 until the extensions 25 and 33 make contact, closing the circuit of the battery 24 and the relay 26. Otherwise, the operation is the same as that described with reference to Fig. 2.

Referring now to Fig. 6, the blade 3 is the single electrode, the electrode 5 having been omitted, and the blade 3 is directly engaged by a handle or the like, not shown, so as to push it toward the tonsil 19. The battery 24 is connected through the wire 27 with an electrode 35 which engages the tonsil 19. The wire 28 extends from the blade 3 to the relay 26 as described, a wire 36 connecting the battery 24 with the relay 26. The wire 22 is connected with the blade 3, and the wire 23 is connected with another electrode 37 which is also adapted to be placed in contact with the tonsil 19. It will appear that when the blade 3 is placed in contact at 19 the circuit of the relay 26 is closed through 3, 28, 36, 24 and 27, whereupon the relay makes the circuit 22, 23 which is completed through the body of the patient at 19.

In the systems having a battery 24 in the relay circuit, the battery might be replaced by a transformer, not shown, the primary coil of which is connected with the system so that the secondary supplies only low-voltage current to the instrument. The transformer should not be grounded.

In this manner an additional safety factor for the patient and for the operator is obtained.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described for obvious modifications 80 will occur to a person skilled in the art.

In the claims affixed to this specification no selection of any particular modification of the invention is intended to the exclusion of other modifications thereof and the right to subse- 85 quently make claim to any modification not covered by these claims is expressly reserved.