Endoscopic instrument with rotatable instrument coupling

A surgical endoscopic instrument has a stem portion and a handle portion and an operating insert axially extending through both of those portions. The insert carries at least one hf operating electrode which can project beyond the distal end of the stem portion. An insulated electrical conductor extends along the length of the operating insert to connect the electrode to a plug subassembly forming the proximal end of the operating insert. The plug subassembly is electrically connected to a removable jack with a connection cable leading to an hf energy source. The operating insert is rotatably supported inside the implement and the jack is non-rotatably coupled to the plug subassembly which is itself non-rotatably linked to the operating insert.

FIELD OF THE INVENTION 
This invention relates to an endoscopic instrument having a high-frequency 
electrode with control means for selectively supplying high frequency 
electrical energy to the electrode. 
BACKGROUND OF THE INVENTION 
Surgical implements with operating electrodes are used in all endoscopic 
interventions, in particular in laparoscopy. As a rule, they are inserted 
by a long stem member through an endoscope duct already in place in the 
body of a patient and serve to cut tissue by application of high-frequency 
(hereafter "hf") energy. 
The electrodes may assume the shapes of blades or plates and frequently are 
in the form of cutting hooks. So-called bipolar devices also are widely 
used, the surgery taking place with two cutting electrodes which, 
typically, are manually and mutually displaceable in the manner of tongs, 
these electrodes being connected to the two terminals of an hf generator 
which supplies hf current between the two terminals. Such implements also 
are called bipolar tongs and illustratively are used in uterine-tube 
suppression. 
During surgery, implements of this general type must be used at various 
angles of rotation, depending on the required direction of cutting. In the 
case of bipolar tongs, sometimes they must be rotated in such a way as to 
be operating perpendicularly to the uterine tube. The implement must then 
be rotated constantly. This feature however is a drawback, because the 
conventional design of such implements offers a reliable grip of the 
surgeon's hand on the driving component only in a given direction. 
Accordingly, the surgery takes place with the hand in a disadvantageous, 
clumsy position, or the hand location must be changed during a surgical 
procedure, a very undesirable necessity. 
Rotatable, operative inserts cannot be used on such implements to solve the 
above problem, because economical and simple implements of this design of 
the state of the art lack the ability to rotate. 
Implements are known which rotatably support the operative electrode and 
which are driven by means of a rotary grip. 
Such an implement is disclosed in European patent document 0,537,574 A2. It 
requires a separate rotary grip and a special eccentric mounting of the 
electrode connector. Accordingly, the implement is comparatively complex 
and susceptible to difficulties. 
German patent document U1 39 17 664 discloses an implement wherein an 
electrical connector is mounted directly at the proximal end of an 
operating electrode. This operating electrode is rotated by a rotary grip 
which drives a stem tube enclosing the operating electrode at the far 
distal end, the tube being non-rotatably coupled to the operating 
electrode and thereby rotating it. Accordingly, the operating electrode is 
rotatably contacted by the electrical connector. This design also is 
unusually complex. 
European patent document 0 596 436 A1 discloses an implement in which a 
rotary grip drives the operating electrode at its proximal end. At that 
location, the electrical connector is non-rotatably seated on the 
operating electrode and moreover it is also non-rotatably connected to the 
rotary grip. In this configuration therefore the connector non-rotatably 
couples the operating electrode and the rotary grip. Again this design is 
highly complex. 
SUMMARY OF THE INVENTION 
An object of the present invention is to provide an economical endoscope 
which also evinces a simple configuration. 
Briefly described, the invention comprises a surgical endoscopic instrument 
having a stem portion, a handle portion and an operational insert having 
at least one high-frequency energized operating electrode movable to 
project beyond a distal end of the stem portion. A plug subassembly forms 
the proximal end of the operating insert. A removable jack is connected to 
a connecting cable and electrically coupled to the plug subassembly. 
Insulated electrical conductors electrically connect the electrode through 
the length of the operating insert to the plug subassembly. The operating 
insert is rotatably supported inside the endoscope, the jack being 
non-rotatably connected to the plug subassembly and the plug subassembly 
being non-rotatably coupled to the operating insert, and the jack forming 
a rotary grip 
Compared to known instruments for similar purposes, the present invention 
is characterized by substantially enhanced simplicity. The electrical 
connector itself is made to be the rotary grip. Therefore the separately 
provided rotary grip of the prior art may be omitted and hence also the 
complex rotary coupling between the electrical connector and the rotary 
grip. The configuration is much simplified thereby and, surprisingly, 
handling is also improved, because the electrical connector, which is 
located on the proximal side, can be better gripped by one hand while the 
implement is held by the other hand than can the rotary grip farther to 
the fore, that is farther distally. 
By rotatably linking the operating insert to the handling portion with a 
disengageable stop, the operating insert may be changed merely by pulling 
it out of the implement, for instance in case of wear or defective 
insulation, or to exchange it with other operating inserts for special 
applications that use cutting electrodes of other shapes. 
By rotatably linking the jack to the handling portion with a disengageable 
stop which is axially stationary, undesired disengagement of the 
electrical contacts during surgery is prevented. 
By shaping the jack as a rotary member with corrugations in a proximal 
segment freely projecting beyond the handling portion, manual rotation is 
facilitated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The figures show bipolar tongs with a stem portion indicated generally at 1 
and a handle portion indicated generally at 2 for manipulating the 
instrument. These portions are interconnected by a bent leaf spring 3 of a 
preselected width which is attached to the stem and handling portions 1 
and 2 such that these portions are longitudinally linked by the spring but 
are not rotatable relative to each other. Conventional slide guides for 
axial alignment and for preventing rotation between the stem and handling 
portions 1 and 2 are omitted for clarity from the drawing. 
The stem portion 1 comprises an insulated (i.e., electrically 
non-conductive) stem tube 4 affixed to the proximal end of a slidable part 
5 supporting the distal end of the leaf spring 3. 
Handle portion 2 comprises a housing 6 having an axial and continuous 
borehole 7 therethrough, the inner diameter of which corresponds to the 
inner diameter of stem tube 4 with which it is flush and coaxially 
aligned. The proximal end of leaf spring 3 is attached to housing 6. 
An operating implement with a sheath tube 8 passes through and is rotatably 
supported in the stem and handle portions 1 and 2. Tube 8 illustratively 
may be metallic for strength. An insulator 9 is at the distal end of, and 
within, sheath tube 8 and houses, for example in a potting material, the 
proximal ends of two resilient tong electrodes 10. 
Tong electrodes 10 are electrically connected within insulator 9 to 
electrical conductors 11 clad with electrical insulation 12 and passing 
through the length of sheath tube 8. 
An electrical connector comprising two longitudinally separated tubular 
insulators 13 and two electrically conductive tubular contacts 14, 
separated from each other by the insulators, projects proximally beyond 
the distal end of sheath tube 8. As shown in the sectional view of FIG. 2, 
the ends of electrical conductors 11 are exposed and each conductor is 
electrically connected to one of contacts 14 on the inside of the tubular 
connector. 
Insulators 13 and contacts 14 are cross-sectionally identical to form a 
first connector similar to a telephone plug somewhat smaller in diameter 
than sheath tube 8 and being of a non-circular cross-section, for instance 
square in the embodiment shown in FIG. 2. 
Electrical connector 13, 14 so formed is connected to a second connector or 
jack 15 and is non-rotatably seated therein by a mating square axial 
recess 16 on the plug sub-assembly. Jack 15 receives two contact springs 
18 in slots 17 adjoining the recess 16, each spring resting in 
electrically contact with one of contacts 14. Contact springs 18 pass 
through the proximal end of insulating jack 15 and are connected to 
electrical conductors 19 of a connecting cable 20 connected to jack 15, 
the cable in turn leading to an hf generator, not shown. 
To ensure reliable guidance and protection against kinking or breaking of 
the connector, jack 15 is rotatably supported at its distal end in a 
concentric annular wall 21 of housing 6 (FIG. 1). In that region, jack 15 
has an external circumferential groove 22 engaged by a locking ball 24 
radially displaceable inside annular wall 21 and pressed inward by a 
spring 23, forming a detent structure for permitting rotation but 
inhibiting relative axial motion. 
Disengageable stop means coupling sheath tube 8 to the handle portion 
includes a stop blade 28 held transversely to the endoscope axis by pins 
26 in arms 25 mounted distally of housing 6 and urged by a spring 29 into 
an annular channel 30 on sheath tube 8, the tube thereby being kept 
stationary in the axial direction while still being rotatable. 
After jack 15 has been removed and stop blade 28 has been released by 
depressing a knob 31 at the end of one of pins 26, the operating device 
can be replaced by another by being pulled out of stem portion 1. 
Following insertion of a stem portion and slipping jack 15 onto the jack 
sub-assembly 13, 14, the implement is ready for operation. 
The surgeon grasps handle portion 2 at leaf spring 3, using his thumb 32, 
index finger 33 and middle finger 34, and then, by compressing the ends of 
leaf spring 3 toward each other, he can displace shaft portion 1 in the 
direction of handle portion 2 within which the operating instrument 
together with its sheath tube 8 is held axially stationary. As a result, 
the distal end of the stem tube 4 moves toward the resilient and 
spaced-apart tong electrodes 10 which it forces together into various 
angular positions relative to each other. 
If the tong electrodes 10 are in a circular angular position other than 
desired relative to the instrument position, i.e., relative to a vertical 
plane through the instrument axis, then the surgeon seizes with his other 
hand jack 15 which has corrugations 35 on the outer surface of its end 
proximally projecting beyond annular wall 21, forming a rotatable grip. By 
means of the cross-sectional locking between recess 16 of jack 15 and plug 
sub-assembly 13, 14, he rotates sheath tube 8 non-rotatably joined to that 
sub-assembly, so that the tong electrodes 10 non-rotatably linked to tube 
8 are also rotated into the desired circular position. 
It should be noted that the instrument of the invention is for use with an 
endoscope or with a tubular device similar to an endoscope in which the 
optics may be separately housed. 
The scope of the invention allows many instrument variations. The implement 
may be unipolar, that is comprising only one, illustratively hook-shaped 
cutting electrode. The remaining design may be identical. Thereby the plug 
sub-assembly is simplified by only one contact 14 being required. Jack 15 
also is commensurately simplified. In such an implement, the longitudinal 
displaceability between shaft portion 1 and handle portion 2 may be 
eliminated. These portions may be connected to each other. 
The non-rotatable coupling of jack 15 to the plug sub-assembly 13, 14 may 
be achieved in another way. For example, in a bipolar implement as shown 
in the Figures, the two contacts may be mounted in axially parallel 
manner, similarly to a household outlet, rather than being axially 
consecutive as the shown contacts 14. This design also secures mutual 
non-rotatability of the components. 
The electric connection also may be implemented in a manner similar to that 
shown but wherein the plug sub-assembly evinces circular cross-sections of 
its parts 13 and 14 with longitudinal flutings or the like which are 
engaged by corresponding locking means for jack 15, for instance the 
contact springs 18, to assure non-rotatability. The structure also may be 
arrange such that, in the presence of excessive torques, there will be 
rotational-stress relief by the springs yielding elastically.