EP0259422A1

EP0259422A1 - Microsurgical instrument for use as gripper or scissors

Info

Publication number: EP0259422A1
Application number: EP87901525A
Authority: EP
Inventors: Khalil Hanna
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-03-18
Filing date: 1987-03-18
Publication date: 1988-03-16
Also published as: WO1987005484A1; FR2595938A1; US4873979A; JPS63502884A

Abstract

Cet instrument comporte deux bras longitudinaux rigides (1 et 2) articulés mutuellement autour d'un axe transversal (7) à leurs extrémités proximales respectives (5, 6) alors que leurs extrémités distales respectives (22 et 23) sont propres à coopérer dans une action de pincement ou de coupe; les bras (1 et 2) présentent des zones respectives d'actionnement manuel (8 et 9) entre l'axe d'articulation (7) et leurs extrémités distales respectives (22 et 23) de même que des moyens (78) de sollicitation élastique des bras (1 et 2) à la rotation relative dans un sens d'écartement mutuel de leurs extrémités distales (22 et 23). Application à la réalisation de pinces ou de ciseaux de grande précision, par exemple à usage de porte-aiguille, de pince avec ou sans griffes, de ciseaux pour greffe de cornée ou de ciseaux d'autres usages.This instrument comprises two rigid longitudinal arms (1 and 2) mutually articulated around a transverse axis (7) at their respective proximal ends (5, 6) while their respective distal ends (22 and 23) are capable of cooperating in a pinching or cutting action; the arms (1 and 2) have respective manual actuation zones (8 and 9) between the hinge pin (7) and their respective distal ends (22 and 23) as well as means (78) for biasing elastic of the arms (1 and 2) to the relative rotation in a direction of mutual spacing of their distal ends (22 and 23). Application to the production of high-precision forceps or scissors, for example for use as needle holders, forceps with or without claws, scissors for corneal grafting or scissors for other uses.

Description

MICROSURGICAL INSTRUMENT FOR PLIERS OR SCISSORS

The present invention relates to a microsurgical instrument for use with forceps or scissors.

More specifically, it relates to such an instrument of a type comprising two rigid longitudinal arms which are articulated mutually around a defined transverse axis and have, on the one hand, respective proximal ends and, on the other hand, respective distal ends, said ends. distal being offset longitudinally relative to said axis and adapted to cooperate in a pinching or cutting action, respectively, by relative rotation of the two arms around said axis in a first direction corresponding to a mutual approximation of said distal ends, the arms having zones respective manual actuation to the relative rotation about said axis in said first direction while there are provided elastic biasing means of the arms to relative rotation about said axis in a second direction opposite to said first direction and corresponding to a mutual spacing of said ends distal.

In their currently known embodiment, instruments of this type are characterized in that the transverse axis of mutual articulation of the two rigid longitudinal arms is located between the proximal ends and the distal ends, generally closer to the distal ends than proximal ends; the manual actuation zones of the arms are then located at the proximal ends, and the means of elastic biasing of the arms consist of two spring blades, each extends approximately longitudinally a respective arm, of which it is integral by the proximal end thereof; the two blades are curved towards each other from the proximal ends of the arms and are articulated on one another at a certain distance from these proximal ends.

Such a structure has a number of drawbacks resulting from the proximity of the axis of mutual articulation of the arms and of the distal ends of the latter.

If the instrument is a needle holder, that is to say a clamp intended for the manipulation of a needle carrying a suture thread, this proximity involves a significant risk of jamming of the thread in the joint, it that is to say breaking of this thread, the fragility of which is great.

If the instrument is a pair of scissors, the arms of which have at their distal ends the shape of blades capable of cooperating in a cutting action by mutual crossing, the proximity of the axis of articulation and of the blades complicates the geometry of these last.

In addition, whether the instrument is designed as a pliers or as a pair of scissors, the proximity of the axis of articulation with respect to the distal ends of the arms necessarily associates with a determined mutual spacing of these ends. distal a relatively large angular offset between the two arms. It follows on the one hand that the movement of the arms in the first direction, that is to say in the sense of mutual approximation of the distal ends, results in a tendency of the latter to expel longitudinally what is between them, whether it is a needle if the instrument is a needle holder pliers, d '' a muscle or tissue if the instrument is a forceps or a pair of scissors, which affects the precision of intervention, which is crucial in the microsurgical field.

It also follows that a determined mutual spacing of the distal ends of the arms corresponds to a much greater mutual spacing of the proximal ends of these arms, since these proximal ends are more distant from the axis of articulation than the ends distal; similarly, to a determined amplitude of movement of mutual approach or mutual spacing of the distal ends corresponds a much greater amplitude of movement of mutual approximation or mutual spacing of the proximal ends where the manual actuation zones of the arms are located. ; this results in a large bulk of the instrument in the surgeon's hand, which results in a certain discomfort in use and in a difficulty in precisely controlling the relative position of the distal ends of the arms; in addition, it is noted that this significant bulk in the surgeon's hand is located along a plane perpendicular to the axis of articulation, while the instrument has parallel dimensions to this axis of much smaller dimensions, so that it is difficult for the surgeon to rotate the instrument on him even in his hand, and forces him to rotate the whole hand with the instrument when a rotation of it on itself is desired.

This drawback is further increased by the fact of the elastic biasing means of the arms in the form of the two aforementioned spring leaves; in fact, to limit the longitudinal dimensions of the instrument, it is provided that the two leaf springs are housed in the surgeon's hand as are the manual actuation zones of the arms; however, to ensure their function, the spring blades are oriented so that they present perpendicularly to a plane perpendicular to the axis of articulation of the arms their widest faces, which ensures a setting of the instrument in the hand ; this setting is generally considered to be a drawback insofar as it becomes practically impossible to rotate the instrument on itself in the hand, even if the possibility of a firm grip of the instrument is moreover desirable.

The object of the present invention is to provide, for a microsurgical instrument for use with pliers or scissors of the type indicated in the preamble, a structure making it possible to remedy all of these drawbacks.

To this end, the present invention provides an instrument of the type indicated in the preamble, characterized in that said transverse axis of mutual articulation of the arms is located at the proximal ends of the latter, and in that said manual actuation zones of the arms are located between said axis and the distal ends of the arms. It will be noted that it has already been proposed, for uses in microsurgery, forceps of the BRUCELLES type, comprising two elastically deformable longitudinal arms, mutually secured at one of their ends; such pliers cannot have the same uses as the instruments of the type targeted by the present invention, because of the inherent flexibility of their arms and because of the absence of a defined axis of relative rotation of the latter, which excludes both a use presupposing the application of relatively large forces by the distal ends of the arms and a use requiring precise control of the relative positions of these distal ends; in particular, the production of scissors by means of such a structure appears to be excluded.

On the other hand, by retaining an axis defined materially, for example by a journal, by way of mutual articulation of the arms and by preserving as rigid as possible the latter, the present invention proposes a structure applicable to high precision instruments , which may also apply significant forces at the distal ends.

To these advantages, the structure of the invention adds a maximum spacing of the articulation axis of the arms with respect to the distal ends of the latter, that is to say the elimination of any risk of jamming. wire if the instrument is made as a needle holder pliers and the possibility of making sharp blades of geometric shape comparatively simpler if it involves making scissors. In addition, the proximity of the manual actuation zones of the arms relative to the distal ends of the latter makes it possible to best control the relative position of the latter and considerably reduce the size of the instrument in the surgeon's hand; in particular, the instrument may have similar dimensions in all transverse directions, whether the distal ends are spaced apart at the maximum or close to each other at the maximum, which considerably facilitates the gripping of the instrument by the surgeon and allows rotation of the instrument on itself in his hand in a particularly convenient, flexible and regular way; in fact, the orientation of the instrument around a longitudinal direction in the hand becomes practically indifferent, which results in a particularly great flexibility of use of the instrument.

According to a preferred embodiment of the instrument according to the invention, the elastic biasing means of the arms comprise at least one compression spring interposed between the arms, between said axis and said distal ends; for example, the elastic biasing means comprise at least one approximately longitudinal leaf spring, curved in a mean plane perpendicular to the axis and having two end zones bearing against one of the arms in respective circumferential directions centered on said axis and an intermediate zone bearing against the other arm in a circumferential direction centered on said axis, between said axis and said distal ends. Then, the elastic biasing means do not constitute any obstacle to the free manipulation of the instrument, whatever their stiffness.

For certain applications, the instrument according to the invention may comprise means of immobilizing, at will, the two arms against a relative rotation about said axis in said second direction, in a relative position of maximum mutual approximation. said distal ends; then, advantageously, these immobilization means may comprise, between said axis and said distal ends, on the one hand a keeper secured to one of the arms and on the other hand a latch mounted with longitudinal sliding on the other arm and manually accessible in the manual actuation zone of this arm to be brought at will into a position of engagement with the strike, to achieve said immobilization, or in a release position vis-à-vis the strike, to remove said immobilization; when the elastic biasing means of the arms comprise a spring leaf disposed as indicated above, this spring leaf advantageously bears via the bolt on the arm carrying this bolt, which makes it possible to ensure so particularly convenient and in a reduced space a snap of the latch in its positions of engagement and disengagement respectively with respect to the keeper, against any accidental longitudinal sliding.

Advantageously, means are provided for limiting the mutual spacing of the distal ends of the arms, as are means for mutual guiding of the arms to relative rotation about their axis of mutual articulation without the possibility of relative translation. parallel to it; advantageously, these means for limiting the mutual spacing of the distal ends of the arms and these means for mutual guiding of the arms to relative rotation are defined by different transverse projection surfaces which the two arms solidly present towards each other, in respective circumferential directions centered on the axis of mutual articulation, between this axis and their distal ends and preferably closer to these distal ends than to the axis; if a lock is provided as indicated above, one of these projections advantageously constitutes the keeper of this lock.

Thus, it is possible to have a particularly complete instrument and, however, using a small number of parts, which allows it to be produced in a small footprint and at a low cost.

In addition, it is understood that the entire mechanism of the instrument can be hidden between the arms of the latter, so that it is possible to give this instrument a simple, functional aesthetic, which can be invariable from an instrument for the use of pliers, whatever the type of pliers, to an instrument for use of scissors, whatever the use of these scissors, if one naturally excludes the shape of the distal ends of the arms, which is adapted to the function of the instrument; thus, thanks to the structure recommended by the present invention, it becomes possible to bring together an aesthetically homogeneous range of instruments adapted to different functions without harming the functional qualities of these instruments. Other characteristics and advantages of the invention will emerge from the description below, relating to several nonlimiting examples of implementation, as well as from the appended drawings which form an integral part of this description.

- Figure 1 shows a side view of a needle holder according to the present invention.

- Figure 2 shows a view of this needle holder partly in section through a median longitudinal plane, perpendicular to the axis of mutual articulation of the two arms of the needle holder and identified in II-II in Figure 1.

- Figure 3 shows a view of the needle holder in the direction of the longitudinal arrow III in Figure 1.

FIGS. 4 and 5 show a view of the needle holder in section through transverse planes marked respectively in IV-IV and V-V in FIG. 2.

- Figure 6 shows a view of the needle holder in the longitudinal direction identified by arrow VI in Figure 1, opposite to the direction of arrow III.

FIG. 7 shows a view of the needle holder in section through a longitudinal plane parallel to the axis of mutual articulation of the two arms and identified in VII -VII in FIG. 4.

- Figure 8 shows a side view of pliers with bent flats, bent, according to the present invention.

- Figure 9 shows a view of this clamp essentially in section through a median longitudinal plane, perpendicular to the axis of mutual articulation of the two arms of the clamp and identified in IX-IX in Figure 8.

- Figure 10 shows, in a view similar to that of Figure 8 but limited to the distal end of the arms, an upper right muscle forceps produced in accordance with the present invention.

FIG. 11 shows a view of the distal ends of this clamp in section through a median longitudinal plane, perpendicular to the axis (not shown) of mutual articulation of its two arms and identified in XI-XI in FIG. 10.

- Figure 12 shows a localized enlargement of Figure 11.

- Figure 13 shows a view of the clamp of Figure 10 along the longitudinal arrow XIII with enlargement greater than that of Figure 12.

- Figure 14 shows a partial view of this clamp along the longitudinal arrow XIV, in the opposite direction to the arrow XIII, on the same scale as in Figure 1 3. - Figure 15 shows, in a partial view similar to that of Figure 10, a claw pliers produced in accordance with the present invention.

- Figure 16 shows this claw pliers in a view similar to that of Figure 11, that is to say in section through a median longitudinal plane perpendicular to the axis of mutual articulation (not shown) of the two arms of the pliers and marked enXVI-XVI in Figure 15.

- Figure 17 shows a greatly enlarged detail of Figure 16. - Figure 18 shows, in an even more greatly enlarged view and along an arrow marked in XVIII, parallel to the not shown axis of mutual articulation of the two arms of the forceps, a claw of the distal end of one of the arms of the latter.

- Figure 19 shows, in a partial view similar to that of Figures 10 and 15, scissors for corneal transplant (left) made in accordance with the present invention.

- Figure 20 shows, in a limited view similar to that of Figures 11 and 16, a view of these scissors essentially in section through a median longitudinal plane perpendicular to the axis (not shown) of mutual articulation of their arm and marked in XX -XX in Figure 19.

FIG. 21 shows a view of these scissors in the direction of the longitudinal arrow XXI in FIG. 19.

- Figure 22 shows a view of the distal ends of the arms of these scissors in section through a plane marked in XXII -XXII in Figure 20. - Figure 23 shows, in a view similar to that of Figures 10, 15, 19 and limited to the distal ends of the arms, another pair of scissors according to the present invention.

- Figure 24 shows, in a limited view similar to that of Figures 11, 16, 20, these scissors essentially in section through a median longitudinal plane perpendicular to the axis (not shown) of mutual articulation of their arms and located in XXIV-XXIV figure 23. - Figure 25 shows a localized enlargement of these scissors seen in the direction of arrow XXV in Figure 23, which arrow is parallel to the axis of mutual articulation of the arms of the scissors. FIG. 26 shows a view of these scissors, in the direction of the longitudinal arrow XXVI of FIG. 23.

In all of the figures, the various instruments according to the invention have been illustrated in the closed state, that is to say when the distal ends of the arms are brought together as much as possible; except where expressly mentioned, the description which follows will be made with reference to this state; however, in Figures 2.9, 11, 16, 20, 24, there is further illustrated the distal end of one of the respective arms in the open position, that is to say of maximum screw spacing -with respect to the distal end of the other respective arm, which is assumed to be immobile for reasons of ease of drawing. In addition, it will be noted on examining all the figures that the different instruments according to the invention which have been illustrated have the same external shape, if we except the distal ends of the arms, intended to cooperate in an action. of pinching or cutting and adapted to this function, as well as large analogies of structure so that we will firstly endeavor to describe all the common points between the different instruments illustrated, before detailing the specific characteristics to each of them. Consequently, reference is firstly made to the assembly of FIGS. 1 to 26 in which there have been illustrated instruments each of which has two arms 1 and 2 elongated in the same longitudinal direction 3 and essentially juxtaposed mutually transversely to this longitudinal direction 3; in the same longitudinal direction 4, the two arms 1 and 2 successively have:

- respective proximal end zones 5, 6 which interpenetrate as will appear later and by which the two arms 1 and 2 are articulated mutually around a transverse axis 7, that is to say perpendicular to the longitudinal direction 3; compared to the longitudinal dimension horstout of the arms 1 and 2, which is advantageously of the order of 12 cm but could naturally be greater or less than this value, the proximal end zones 5 and 6 of the arms 1 and 2 have a dimension weak longitudinal, preferably less than 1 cm without this indication being considered as limiting;

- respective zones 8, 9 intended for gripping the instrument and constituting respective zones of manual actuation of the two arms 1 and 2 to the relative rotation around the axis 7 in the direction of mutual approximation of the zones of these arms 1 and 2 other than their proximal end zones 5 and 6, by manual application to the two zones 8 and 9 of respective forces of direction 10 and 11 antagonistic, transverse, and more precisely approximately perpendicular to a longitudinal plane 12 including axis 7; for this purpose, the manual actuation zones 8 and 9 have a longitudinal dimension advantageously greater than half of the overall longitudinal dimension of the arms, and for example of the order of 2/3 of this dimension, that is to say in the order of 7 to 8 cm in the example indicated above, although these figures are only a non-limiting indication; in addition, in the manual actuation zones 8 and 9, the two arms 1 and 2 considered in the closed position of the instrument together have, in any transverse cutting plane, a constant external contour, for example circular of not shown or, preferably, elliptical as illustrated, for example, in FIGS. 3 to 6, 13, 21, 26; then, the major axis of the ellipse is located in the plane 12 while the minor axis of this ellipse is located along a longitudinal plane 13 perpendicular to the plane 12 as well as to the axis 7 (this plane 13 merges with the section plans II-II, IX-IX, XI-XI, XVI-XVI, XX-XX, XXIV-XXIV); this contour of the arms 1 and 2 in their manual actuation zones 8 and 9 is defined by external faces 14 and 15 which the arms 1 and 2 have respectively in these zones 8 and 9, the faces 14 and 15 being one and the other symmetrical with respect to the plane 13 while they are symmetrical with one another with respect to the plane 12 and are connected along the latter to respective plane faces 16 and 17 which are placed opposite one of the other when the instrument is in the closed position and are then either arranged along the plane 12 along which they are joined, in a manner not illustrated, or arranged in close proximity diate of the plane 12 but recessed from it, to which they are parallel, as illustrated for example in Figures 2, 3 to 6.9, 11 to 13, 16, 17, 20, 21, 24, 26 ; in this case, the relative spacing between the faces 16 and 17 perpendicular to the plane 12, however, preferably remains limited to a value less than a millimeter; to facilitate gripping of the instrument by the manual actuation zones 8 and 9 of the arms 1 and 2, the faces 14 and 15 of the latter advantageously have a coating or an anti-slip treatment, in a manner known in it -even ; by way of nonlimiting example, the transverse dimensions of the instrument in the manual actuation zones 8 and 9 of the arms 1 and 2 are advantageously less than 1 cm; in the case of an elliptical section, a dimension of the order of 8 mm has been chosen along the plane 12, that is to say parallel to the axis 7, and a dimension of the order of 7 mm perpendicular to plane 12, the instrument being assumed to be in the closed position, but these currently preferred figures are only a non-limiting indication;

- respective intermediate zones 18 and 19 in which the faces 16 and 17 continue coplanarly whereas, on the other hand, the faces 14 and 15 succeed respectively, in direction 4, conical faces 20 and 21 which converge in direction 4 in retaining symmetry with respect to planes 12 and 13, the instrument being assumed to be in the closed position, so as to define a progressive external thinning of the instrument in direction 4; - respective distal end zones which differ from one instrument to another whereas the zones previously described 5, 6, 8, 9, 18, 19 may in turn be identical from one instrument to another; the respective distal end zones of the arms 1 and 2 have been designated by the references 22 and 23 as regards the needle holder illustrated in FIGS. 1 to 7, 24 and 25 as regards the needle-nose pliers illustrated in the figures 8 and 9, 26 and 27 with regard to the upper straight muscle forceps illustrated in FIGS. 10 to 14, 28 and 29 with regard to the claw forceps illustrated in FIGS. 15 to 18, 30 and 31 with regard to the scissors illustrated in Figures 19-22, 32 and 33 with respect to the scissors illustrated in Figures 23-26; the respective shapes of these different distal zones will be described later in detail; it will be noted, however, that, in common with all the instruments illustrated, in the immediate vicinity of the transition between the intermediate zones 18 and 19 and the aforementioned disdistal end zones succeed the faces 16 and 17 respectively, possibly disjoint when the clamp is in closed state, flat faces 34 and 35 of arms 1 and 2, which faces 34 and 35 are located along respective planes including axis 7 and merging with plane 12 when the instrument is closed, so that mutual support of the faces 34 and 35 along this plane 12 then intervenes to limit the relative pivoting of the arms 1 and 2 around the axis 7 in the direction 10, 11 of mutual approximation, in particular of the respective distal ends of the two arms. Advantageously, the different respective zones of the arms 1 and 2 which have just been described are made in a single piece of material as rigid as possible, for example of treated steel, and means are provided to prevent any relative displacement. arms parallel to the axis 7 of their mutual articulation, so that the distal ends of the arms can only move relative to each other in a relative rotational movement around the axis 7, d '' a way perfectly controlled by the surgeon.

In the preferred embodiment illustrated, by way of nonlimiting example, such means are provided on the one hand at the level of the respective proximal end zones 5 and 6 of the two arms 1 and 2, and on the other hand in the manual actuation zones 8 and 9 of these arms, and more precisely in the immediate vicinity of the transition of these zones 8 and 9 with the intermediate zones 18 and 19, respectively. More specifically, in its proximal end zone 5, the arm 1 has the shape of two flat longitudinal legs 36 and 37, having respective mean planes 38 and 39 perpendicular to the axis 7; these two tabs 36 and 37 are arranged symmetrically to one another with respect to the plane 13 and have, towards each other, that is to say towards this plane, respective faces 40 and 41 plane, mutually parallel, perpendicular to the axis 7 and symmetrical to each other with respect to the plane 13; we note that the two legs 36 and 37 form a projection towards the other arm 2 relative to the face 16 of the arm 1, such so that the axis 7 is intersecting the faces 40 and 41; along the axis 7, the two tabs 36 and 37 are pierced with respective bores 42 and 43, cylindrical of revolution around the axis 7 with the same diameter. In its proximal end zone 6, the arm 2 has the shape of a single leg

44 longitudinal, also flat, the plane 13 of which constitutes a mean plane; this tab 44 forms a projection towards the arm 1 relative to the face 17 of the arm 2 and it intersects the axis 7; perpendicular thereto, it has in the direction of a distance from the plane 13 two faces 45, 46 planes, mutually parallel, symmetrical to each other with respect to the plane 13, with a mutual spacing perpendicular to this plane substantially identical to the mutual spacing of the faces 40 and 41 with which the faces

45 and 46 are respectively in contact with the possibility of relative sliding with a minimum of obstacles; along axis 7, the tab 44 is pierced right through with a cylindrical bore 47 of revolution around the axis 7 with a diameter identical to the respective diameters of the bores 42 and 43, and the three bores 42, 47, 43 as well aligned along the axis 7 receive a common journal 48, of a diameter substantially identical to the common diameter of the bores 42, 47, 43; this pin 48 is immobilized by any appropriate means, known to a person skilled in the art, in the bore 42 and / or the bore 43, in which case it is mounted on the other hand free inside the bore 47, or well the pin 48 is secured by any means known to a person skilled in the art with the tab 44 inside the bore 47 then that it is on the other hand free vis-à-vis the two bores 42 and 43, so that this pin 48 provides guidance of the two arms 1 and 2 to relative rotation about the axis 7 with a minimum of shackles. Naturally, other means could be provided for guiding the two arms 1 and 2 to relative rotation about an axis 7 perfectly defined in its position relative to the two arms 1 and 2, in the zones of proximal ends. 5 and 6, without thereby departing from the scope of the present invention.

In the manual actuation zones 8 and 9 of the two arms 1 and 2, and more specifically in the immediate vicinity of the connection of these zones 8 and 9 with the intermediate zones 18 and 19, the means provided in the example illustrated to prevent relative movement of the arms parallel to the axis 7 are defined by transverse projections 49 and 50 which the arms 1 and 2 respectively present towards each other, in an integral manner but advantageously in an added form for example by screwing as schematized it respectively in 51 and 52; the two projections 49 and 50 are arranged in respective mean directions situated in the plane 13, circumferential and centered on the axis 7 of mutual articulation of the arms 1 and 2, which directions are comparable to rectilinear directions, respectively 53 and 54 , perpendicular to the plane 12 when the instrument is closed; each of the protrusions 49 and 50 is symmetrical relative to the plane 13, and these two protrusions are offset longitudinally relative to each other so that the protrusion 49, located at the junction between the manual actuation zone 8 of arm 1 and the intermediate zone 18 of the latter, penetrates beyond the face 16 into a recess 55 which the arm 2 presents opposite, recessed in relation to its face 17, in the circumferential mean direction 53 of the projection 49, and that the projection 50, located between the projection 49 and the axis 7 although being nevertheless closer to the distal ends of the arms than this axis 7, penetrates beyond the face 17 in a recess 56 provided in the face 16 arm 1, in the circumferential mean direction 54 of this projection 50, it being understood that the instrument is considered in the closed state; the projections 49 and 50 are freely received in the respective corresponding recesses 55 and 56 so as not to constitute an obstacle to the relative pivoting of the arms 1 and 2 around the axis 7.

It will be noted that the recess 56 extends longitudinally in the direction 4 further than is necessary to receive the projection 50, and also receives, however integral with the arm 1, the insert defining the projection 49 in the example of preferred implementation which has been illustrated.

Towards the projection 50 in a longitudinal direction, that is to say in the opposite direction to the direction 4, the projection 49 ends in an approximately longitudinal edge 57 having the general shape of a stirrup, a flat area 58 of which is disposed substantially perpendicular to the plane 13, symmetrically on either side of it, inside the recess 55 of the arm 2 if we assume the instrument closed, and connects two other flat areas 59 and 60 arranged as to them parallel to plane 13, in posi respective symmetrical to one another with respect to this plane, both in the recess 55 of the arm 2, if the instrument is assumed to be closed, and in the recess 56 of the arm 1; the shape of the zones 59 and 60 of the rim 57 is more particularly visible in FIG. 8.

The zone 58 of the rim 57 has towards the plane 12, the instrument being assumed to be closed, a flat face 61 parallel to this plane 12 while the zones 59 and 60 of the rim 57 have towards the plane 13 respective flat faces 62 and 63 parallel to this plane 13 and symmetrical to each other with respect to it.

Complementarily, the projection 50 has longitudinally towards the projection 49, that is to say in direction 4, an approximately longitudinal edge 64 disposed in the recess 56 when the instrument is in the closed state; the rim 64 engages between the zones 59 and 60 of the rim 57 of the projection 49 and comes into contact with the respective faces 62 and 63 of these zones by planar faces, respectively 65 and 66, parallel to the plane 13 and turned in the direction of a distance with respect thereto, with a mutual spacing of the faces 65 and 66 perpendicular to the plane 13 substantially identical to the relative spacing of the faces 62 and 63 parallel to this plane so that they are established between the face 65 and the face 62, on the one hand, between the face 66 and the face 63, on the other hand, contacts with the possibility of relative sliding which ensure that the two arms 1 and 2, as close as possible to their ends respective distals, a relative movement ban parallel to the axis 7 without however obstructing the relative rotation of the two arms around this axis 7; in addition, facing the face 61 of the zone 58 of the rim 57 in a circumferential direction centered on the axis 7 and comparable to a straight direction 67 and perpendicular to the plane 12 when the instrument is closed, the rim 64 has a planar face 68 at least approximately parallel to the plane 12 and spaced from the face 61 perpendicular to this plane when the instrument is in the closed state while being capable of approaching the face 61 until it comes into contact with it when , by relative pivoting of the arms 1 and 2 around the axis 7, in the direction of a relative spacing of the manual actuation zones 8 and 9 of the arms, their intermediate zones 18 and 19 and their respective distal ends, the instrument is opened; the respective faces 61 and 68 of the zone 58 of the rim 57 and the rim 64 thus constitute abutment surfaces limiting the angular offset between the arms 1 and 2 when the instrument opens, that is to say also the mutual spacing of the distal ends of the arms 1 and 2 during this opening; Figures 2.9, 11, 12, 16, 17, 20, 24, we partially illustrated the limit position thus imposed on the distal end 23, 25, 27, 29, 31, 33 of the arm 2 relative to the distal end 22, 24, 26, 28, 30, 32 of the arm 1 at the opening of the instrument; it will be noted that the edges 57 and 64 of the projections 49 and 50 are identically found in the embodiments illustrated in all of FIGS. 1 to 18, so that the distal ends of the arms of the instruments respectively correspondents are separated from each other in an identical manner when these instruments are open, for example by a maximum distance, measured at the distal ends, of the order of 6 mm; this indication is however in no way limiting; on the other hand, in the case of the two embodiments illustrated respectively in FIGS. 19 to 22 and in FIGS. 23 to 26, corresponding to scissors, the projection 49 is identical, including as regards its rim 57, to the projection 49 which comes to be described but the face 68 of the projection 50 is less offset relative to the face 16 of the arm 1 since it is in fact practically coplanar with this face 16; the spacing between the faces 68 and 61, perpendicular to the plane 12, when the instrument is closed is consequently smaller, so that the coming into mutual abutment of the faces 68 and 61 corresponds to a lesser angular offset of the arms 1 and 2 around the axis 7, that is to say at a smaller mutual spacing of the distal ends 30 and 31 or 32 and 33 of the arms 1 and 2 in the case of these two embodiments; by way of nonlimiting example, the maximum value of this mutual spacing, measured at the distal ends, can be of the order of 3 mm; on the other hand, we find in the case of these two embodiments all the other arrangements already described more particularly with reference to the embodiments of FIGS. 1 to 8, and which are also found in the embodiments of FIGS. 9 to 19. The means which have just been described, intended to prevent a relative itoative of the arms 1 and 2 parallel to the axis 7 and to limit the angular movement of these arms around this axis, correspond to a currently preferred embodiment. ; they could however be replaced by other means having the same function, without leaving it the scope of the present invention; in certain cases, in particular when less precision is required, the cooperation of the faces 45 and 46 of the tab 44 of the arm 2 with the faces 40 and 41 of the legs 36 and 37 of the arm 1 could be sufficient to prevent relative movement of the distal ends of the arms 1 and 2 parallel to the axis 7, other means the production of which is within the domain of the skills of a person skilled in the art can also be provided for this purpose; Similarly, one could for example provide for limiting the relative angular movement of the arms 1 and 2 to the opening of the instrument by acting not closer to the distal ends than to the axis 7 as is preferred and as this has been described, but close to this axis 7, for example using for this purpose the tabs 36, 37, 44 which constitute for the two arms 1 and 2 respective narrowing, in a direction parallel to the axis 7; therefore, in particular, the lug 44 is connected to the manual actuation zone 9 of the arm 2 by means of two faces

69 and 70 planes, coplanar, perpendicular to the plane 13 as well as to the plane 12 when the instrument is closed, and disposed respectively on either side of the tab 44; similarly, between the legs 36 and 37, at the connection of the latter with the manual actuation zone 8, the arm 1 has a flat face 71, perpendicular to the plane 13 as well as to the plane 12 when the instrument is closed; longitudinally opposite the faces 69, 70, 71, respectively, the tabs 36, 37, 44 have respective flat faces 73, 74, 75 perpendicular to the plane 13 as well as to the plane 12 when the instrument is closed; faces 73 to 75 are respec tively spaced longitudinally from the faces 69 to 71 when the instrument is thus closed, but are capable of approaching it in respective circumferential directions until they come to abut respectively against these faces by relative warping, during the relative pivoting of the arms 1 and 2 around the axis 7 in the direction of the opening of the instrument, that is to say a mutual spacing of the distal ends; this effect can be used to limit the angular movement of the two arms 1 and 2 at the opening, instead of the cooperation between the faces 61 and 68 of the projections 49 and 50; when, on the other hand, it is not desired to use such a mutual abutment of the faces 69 to 71 and of the faces 73 to 75 to limit the angular movement of the arms 1 and 2, as is the case in the example illustrated, we give at the relative longitudinal spacing between the faces 69 and 73, 70 and 74, 71 and 75 when the instrument is closed, a value large enough so that no contact is established between these faces until the face 68 of the rim of the projection 50 comes into abutment against the face 61 of the rim of the projection 49. It is easily understood that the manual application of forces in the directions indicated in 10 and 11 on the respective zones 8 and 9 of manual actuation of the arms 1 and 2 allow the latter to be brought into a relative position for closing the instrument. To cause the opening thereof are provided elastic biasing means preferably constituted by at least one compression spring interposed between the arms 1 and 2 between the axis 7 of their mutual articulation and their distal ends respective, although other modes of elastic stressing of the arms can be provided without departing from the scope of the present invention.

In the example illustrated, the elastic biasing means are arranged between the respective zones 8 and 9 for manual actuation of the arms 1 and 2, between the axis 7 and the projection 50 closest to the latter, and are more precisely housed partly in a recess 76 that the face 17 of the arm 2 has between the projection 50 and the connection of the manual actuation zone 9 with the distal end zone 6, and partly in a longitudinal extension of the recess 56 up to the level of the connection of the zone 8 for manual actuation of the arm 1 with the proximal end zone 5 of the latter in the case of the embodiment of FIGS. 1 to 7, or in an independent recess 77 of the recess 56 and arranged in the face 16 between this recess 56 and the connection of the zone 8 of manual actuation of the arm with the proximal end zone 5 of the latter in the case of the embodiments of FIGS. 8 to 26.

More specifically, in the example illustrated, the means for elastic biasing of the arms in the direction of opening of the instrument comprise at least one leaf spring, here unique and designated by the reference 78, arranged approximately longitudinally along a plane means coinciding with the plane 13, in which it is curved so as to present two end zones 79 and 80 in abutment against the arm 1 respectively near the connection of the zone 8 of manual actuation of the latter with the zone from ex proximal end 5 thereof and near the projection 50, and an intermediate zone 81 in antagonistic abutment against the other arm 2, approximately halfway, longitudinally, between the end zones 79 and 80, in the recess 76.

These supports are effected by means of respective generators of the leaf spring 78, which generators are parallel to the axis 7, on respective bearing faces 82 (for the end zone 79), 83 (for the end zone 80) and 84 (for the intermediate zone 81) parallel to the plane 12 when the instrument is closed, so that the leaf spring thus applies to the arms 1 and 2, through its zones 79, 80, 84, antagonistic forces in respective circumferential directions, centered on the axis 7.

More specifically, the bearing face 82 for the end zone 79 of the spring leaf 78 on the arm 1 is integral with the latter, parallel to the face 16 but recessed with respect to the latter inwards of the extension of the recess 56 in the case of the embodiment of FIGS. 1 to 7 or towards the interior of the recess 77 in the case of the embodiments of FIGS. 3 to 26; similarly, the bearing face 84 of the intermediate zone 81 of the spring leaf 78 on the arm 2 is integral with the latter, parallel to the face 17 of this arm, set back relative to this face 17 to constitute a bottom face of the recess 76; this bottom face 84 of the recess 76 is connected to the face 17 of the arm 2, respectively on either side of the plane 13, by two planar faces 85 and 86, more particularly visible in FIG. 5, which faces 85 and 86 are parallel to plane 13 and symmetrical with respect to each other and constitute stops for the spring leaf 78 preventing this blade 78 to move parallel to the axis 7 with respect to the arm 2, without however constituting a hindrance to a free elastic movement of the blade 78 in circumferential directions centered on the axis 7; the faces 85 and 86 are also connected to each other by two transverse faces 88 and 89 which also connect the face 84 to the face 17 and define the ends of the recess 76; longitudinally opposite the faces 88 and 89, the end zones 79 and 80 of the leaf spring 78 are curved towards the inside of the recess 76 so that the faces 88 and 89 constitute for the leaf spring 78 stops preventing practically any longitudinal movement of the leaf spring 78 inside the recess 76, with respect to the arm 2 as well as with respect to the arm 1.

The support face 83 of the end 80 of the leaf spring 78 on the arm 1 is, like the support face 82 of the end zone 79 on this same arm 1, arranged parallel to the face 16 of the arm 1, set back relative to this face 16 and for example, as illustrated, coplanarly with the bearing face 82.

However, the bearing face 83 is produced differently on the one hand in the embodiment of FIGS. 1 to 7, and on the other hand in the case of the embodiments of FIGS. 8 to 26. In the case of the embodiments of FIGS. 8 to 26, the bearing face 83 is defined by a partition. transverse 87 secured to the arm 1, and mutually separating the recesses 56 and 77, near the projection 50, so that the bearing face 83 is fixed relative to the arm 1.

By cons, in the case of the embodiment of Figures 1 to 8, the bearing face 83 is movable longitudinally relative to the arm 1, while retaining its parallelism with respect to the face 16 thereof and its spacing with respect to this face 16, that is to say its coplanarity with the bearing face 82 in the example illustrated.

In fact, in the embodiment of FIGS. 1 to 7, the bearing face 83 of the end 81 of the leaf spring 78 on the arm 1 is defined by one face of a latch 90 mounted with longitudinal sliding the along the arm 1 in order to be able to occupy with respect to the latter on the one hand a locked position in which it is illustrated in the figures, and in which it engages with a keeper preferably formed by the projection 50 to immobilize the two arms 1 and 2 against a relative rotation about the axis 7 in their closed positions of the instrument, and on the other hand a release position with respect to the striker to release the two arms 1 and 2 with respect to such a rotation, naturally within the limits authorized by the stops constituted by the faces 61 and 68 respectively of the flange 57 of the projection 49 and of the flange 64 of the projection 50. To this end, the lock 90 is accessible in the zone 8 for manual actuation of the arm 1, by a control button 91.

More precisely, as is apparent from FIGS. 1, 4, 5, the longitudinal extension of the recess 56 beyond the projection 50 towards the proximal end 5 of the arm 1 has a flat bottom face 92, parallel to the face 16 of arm 1 and set back with respect to this face 16, as well as with respect to the bearing face 82 of the end region 79 of the leaf spring 78, and two lateral faces 93 and 94 planes, symmetrical to each other with respect to the plane 13 to which they are parallel, being spaced mutually perpendicular to this plane by a distance identical to the distance separating the faces 85 and 86 perpendicular to this plane, so that the faces 93 and 94 connect the bottom face 92 of the recess 56 to the face 16 of the arm 1 in the respective coplanar extensions of the faces 85 and 86 of the recess 76.

Additionally, the latch 90 is delimited transversely, in addition to the bearing face 83, by a flat face 95 parallel to the face 83 and applied against the face 92, in sliding contact, and by two planar faces 96 and 97 perpendicular to the faces 83 and 95 and arranged parallel to each other, respectively on either side of the plane 13 and symmetrically with respect to each other, in contact respectively with the lateral face 93 and with the lateral face 94 with possibility of relative sliding; in a longitudinal direction opposite to direction 4, the faces 83, 95, 96, 97 of the latch 90 are connected together by a flat transverse face 98 whereas, in direction 4, that is to say towards the projection 50, they are connected to each other by a planar transverse face 99 integrally, protruding longitudinally in direction 4 relative to them, two longitudinal arms 100 and 101 arranged symmetrically to each other with respect to the plane 13, respectively along the lateral faces 93 and 94 of the recess 56, leaving between them a longitudinal intermediate space 202, open in the direction 4 towards the projection 50 to communicate to the lock the shape of a fork when viewed in a circumferential direction centered on the axis 7; the two arms 100 and 101 are delimited on the one hand by coplanar extensions of the face 83 and on the other hand, towards the bottom face 92 of the recess 56, by respective flat faces 102 and 103 coplanar, parallel to the face 95 but set back relative to the latter towards the face 83 so that there remains a space respectively between each of these faces 102 and 103 and the face 92 of the recess 56.

In addition, as is also more particularly apparent from FIGS. 4 and 7, the projection 50 extends respectively on either side of the plane 13, perpendicular to it, over a distance less than the distance separating from this plane. the lateral faces 93 and 94 of the recess 56 and, more precisely, at most equal to the distance separating from this plane the two arms 100 and 101 so that the latter, in the locking position, engage respectively by hand and other of the projection 50, received in the recess 56 when the arms 1 and 2 occupy their relative position for closing the instrument; in this position, the projection 50 has along the bottom face 92 of the recess 56 two flanges 104 and 105 situated respectively on either side of this projection 50 in a direction parallel to the axis 7, and which are inserted between the bottom face 92 and, respectively, the face 102 of the arm

100 and the face 103 of the arm 101, practically without play; this results in the desired locking of the instrument in the closed position, as soon as the lock 90 is retained pressed by its face 95 against the bottom face 32 of the recess 56.

For this purpose, the button 91 is essentially arranged opposite the face 14 of the manual actuation zone 8, in a symmetrical arrangement with respect to the plane 13, and it is integrally connected to the latch 90 by a constricted zone 106 also symmetrical with respect to the plane 13 but having dimensions perpendicular thereto of dimensions smaller than those of the rest of the button 91 as well as at the distance separating the faces 96 and 97 of the lock 90 perpendicular to the plane 13; the constricted area 106 crosses the arm 1, from the face 14 to the bottom face 92 of the recess 56, via a longitudinal slot 107 delimited in the direction of a distance from the plane 13 by two plane faces 108 and 109 , parallel to plane 13 and arranged symmetrically with respect to each other, with a mutual spacing less than the mutual spacing of the faces 96 and 97 of the lock and that of the lateral faces 93 and 94 of the recess 56 as well as the dimensions that the button 91 has perpendicular to the plane 13 in contact with the face 14 of the manual actuation zone 8, however being greater than the dimensions of the throttled zone 106 perpendicular cularily to plan 13; thus, the latch 90 and the button 91 enclose between them, respectively on either side of the constricted area 106, marginal areas of the light 107 with the possibility of longitudinal sliding along these areas without other possibility of movement.

Longitudinally, the light 107, the recess 56, the lock 90 have respective dimensions such that, by sliding the throttled zone 106 of the button 91 in the light 7 and sliding the lock 90 in the recess 56, it is possible to bring the latch 90 either in its locking position in which the arms 100 and 101 immobilize the projection 50 inside the recess 56 as shown, or in a position in which the fingers 100 and 101 are integrally offset longitudinally by relative to the projection 50 to release the latter for a relative rotation of the two arms 1 and 2 about the axis 7 in the direction of a mutual separation of the distal ends 22 and 23 of these arms.

By pressing against the face 83 by its end 80, the leaf spring 78 prevents an untimely sliding of the bolt 90 - button 91 assembly in one direction or the other; preferably, as illustrated, the lock 90 is immobilized in two positions corresponding respectively to the coupling of the arms 100 and 101 with the flanges 104 and 105 of the projection 50 and to the release of this projection 50; for this purpose, the face 83 has two depressions 110 and 111 arranged so that the leaf spring 78 engages therein at its end 80, in an elastic bearing relationship in a circumferential direction centered on the axis 7, respectively in one and the other of the above positions of the lock 90. Naturally, other modes of mutual locking of the arms 1 and 2 of an instrument according to the present invention could be adopted without departing from the scope of this invention; note however the extremely simple form in which we have grouped, in the embodiment of Figures 1 to 8, such means with means for limiting the mutual spacing of the distal ends of the arms in the open position of the instrument and means for preventing relative movement of the distal ends of the arms parallel to the axis of their mutual articulation.

Likewise, although means have been illustrated and described for locking the two arms in the closed position of the instrument exclusively in the case of the embodiment of FIGS. 1 to 8, a

Those skilled in the art will readily understand that such means could also be provided in the case of the instruments illustrated in Figures 10 to 26, just as the instrument illustrated in Figures 1 to 8 could be devoid of locking means.

Having thus described the actual or potential common points between the different instruments illustrated in FIGS. 1 to 26, we will now describe the specific characteristics of each of them, namely the shape of their respective distal ends, by way of nonlimiting examples. microsurgical instruments which can be produced in accordance with the present invention. In the case of the instrument illustrated in FIGS. 1 to 7, namely a needle holder, the distal ends 22 and 23 of the arms 1 and 2 of the instrument have a generally rectilinear shape in an average direction 112 situated in the plane 12 and deviating from the plane 13 in the direction 4, forming with the plane 13 an angle α for example between 30 and 45 °; the distal ends 22 and 23 in this case have the shape of tapered beaks, having one towards the other of the respective flat faces 113 and 114 extending coplanarly respectively the faces 34 and 35, that is to say adjoining mutually in the closed position of the instrument illustrated in particular in Figure 2; in a manner known per se, the faces 113 and 114 may be provided with a recess or a boss facilitating the holding of a curved needle. The distal ends 24 and 25 of the forceps illustrated in FIGS. 8 and 9 also have a rectilinear shape of medium direction 115 diverging in the direction 4 with respect to the plane 13 by forming with respect to the latter an angle β of l 'about 30 to 45 °, the mean direction 115 also being located in the plane 12 if we assume the instrument closed; in the case of this instrument, the distal ends 24 and 25 have respective flat faces 116 and 117 devoid of any relief and any hollow, coplanarly extending the faces 34 and 35 respectively so as to s' adjoin each other along plane 12 when the instrument is closed. The respective distal ends 26 and 27 of the arms 1 and 2 of the upper straight muscle forceps illustrated in FIGS. 10 to 14 also have a generally rectilinear general shape of mean direction 118 diverging in the direction 4 with respect to the plane 13, however forming by with respect thereto an angle γ between 45 and 60 °; the instrument being considered in the closed state, the mean direction 118 is also situated along the plane 12 along which the distal ends 26 and 27 are joined by respective plane faces 119 and 120 extending coplanarly respectively the faces 34 and 35; however, in the case of this embodiment of an instrument according to the present invention, and as appears more particularly from the examination of FIGS. 13 to 14, the respective distal ends 26 and 27 of the arms 1 and 2 have in end, in respective circumferential directions centered on the axis 7, respectively two claws 121 projecting from the face 119 and juxtaposed perpendicular to the direction 118, and a claw 122 projecting from the face 120, which claw 122 is interposed between the two claws 121 when the clamp is in the closed state but is completely released from these claws 121 when the clamp is in the open state. The respective distal ends 28 and

29 of the arms 1 and 2 of the claw pliers illustrated in FIGS. 15 to 18 have a mean longitudinal direction, with a rectilinear shape tapered in the longitudinal direction 4; when the clamp is in the closed state, the distal ends 28 and 29 are in mutual contact, along the plane 12, by respective faces 123 and 124 coplanarly extending the faces 34 and 35 respectively; as is better seen from FIGS. 17 and 18, the face 123 projecting, at the end, a claw 125 arranged along the plane 13 while the face 124 has protruding, at the end, two claws 126 arranged symmetrically one of the 'other with respect to the plane 13 to be placed respectively on either side of the claw 125 when the clamp is in the closed state; when the clamp is in the open state, the claws 126 completely release the claw 125.

In the case of these various instruments, illustrated in FIGS. 1 to 18, the distal ends of the arms therefore consist of nozzles capable of cooperating in a pinching action by mutual contact in a circαnferential direction centered on the axis 7 and, possibly, mutual overlapping of claws due to a relative rotation of the arms tending to close the instrument.

The two embodiments illustrated in Figures 19 to 26 correspond to cases in which the distal ends of the arms have the shape of blades capable of cooperating in a cutting action by mutual crossing in such a circumferential direction and mutual contact according to a direction parallel to the axis 7 due to a relative rotation of the arms 1 and 2 in the direction of closing the instrument.

More specifically, in the case of the embodiment illustrated in FIGS. 19 to 22, the distal ends 30 and 31 of the arms 1 and 2 are closely juxtaposed in a direction parallel to the axis 7 (not visible in these figures) when the ins trument is in the closed state; then, they are directed in a common mean direction 127 which, when the instrument is seen perpendicular to the plane 13 as it is in FIG. 21, appears rectilinear and diverges with respect to the plane 12 in the direction 4, of the same side of this plane 12 that the arm 1 by closing with respect to the plane 12 an angle δ for example of the order of 30 °; on the other hand, when the instrument is seen perpendicular to the plane 12 as is the case in FIG. 20 or even longitudinally as it is the case in FIG. 22, the distal ends 30 and 31 juxtaposed in a direction parallel to the axis 7 when the instrument is closed have a curvilinear mean direction, gradually diverging from the plane 13, on the side thereof corresponding to the distal end 31 of the arm 2.

In this case, to allow the relative pivoting movements of the two arms 1 and 2 around the axis 1, the distal ends 30 and 31 have respective faces 128 and 129 towards each other defined by respective circular generatrices , centered on the axis 7 while, the instrument being assumed to be in the open state as partially shown in FIG. 21, these distal ends 30 and 31 have respective cutting edges 130 towards each other and 131 antagonists, oriented in circumferential directions centered on the axis 7 and in opposite directions in these circumferential directions. The determination of the precise geometry of the faces 128 and 129 and the cutting edges 130 and 131 of the respective distal ends 30 and 31 of the arms 1 and 2 of the instrument illustrated in FIGS. 19 to 22 is in the domain of normal aptitudes of a person skilled in the art, knowing in particular the distance separating these faces or cutting edges from the 'axis 7 of mutual articulation of the two arms and the shape of the incisions to be made using scissors.

FIGS. 23 to 26 illustrate another type of scissors, in which the respective distal ends 32 and 33 are arranged, when the instrument is closed, in the same mean direction situated in the plane 12 but diverging progressively from the plane 13 in direction 4, on the side of the distal end 32 of the arm 1, with a curvilinear shape; when the scissors are in the closed state, the distal zones 32 and 33 in the form of blades are juxtaposed parallel to the axis 7 by respective faces 132, 133 defined by circumferential generatrices centered on the axis 7 whereas, when the arms 1 and 2 are in an open position of the scissors, these distal ends in the form of blades 32 and 33 have, towards each other, in circumferential directions centered on the axis 7, respective cutting edges 134 and 135; in this case also, the determination of the respective shapes 132 and 133 and of the cutting edges 134 and 135 is in the domain of the normal skills of a person skilled in the art.

As said above, the embodiments of the present invention which have just been described are in no way limiting and, in particular, the directions could be oriented differently. beaks or blades constituting the respective distal ends of the instruments which have been described, for example for making a forceps of the upper left muscle from the forceps described with reference to FIGS. 11 to 14, or scissors for corneal graft (right) to starting from the scissors described with reference to FIGS. 19 to 22.

Claims

1. Microsurgical instrument for use with forceps or scissors, comprising two rigid longitudinal arms (1, 2) which are articulated mutually around a defined transverse axis (7) and have, on the one hand, respective proximal ends (5, 6 ) and on the other hand of the respective distal ends (22 to 33), said distal ends (22 to 33) being offset longitudinally with respect to said axis (7) and adapted to cooperate in a pinching or cutting action, respectively, by relative rotation of the two arms (1, 2) around said axis (7) in a first direction (10, 11) corresponding to a mutual approach of said distal ends (22 to 33), the arms (1, 2) having respective zones (8, 9) of manual actuation with relative rotation about said axis (7) in said first direction (10, 11) while means (78) are provided for elastic biasing of the arms (1, 2) upon rotation relative around said axis (7) in a second direction i nverse of said first direction (10, 11) and corresponding to a mutual spacing of said distal ends (22 to 33), characterized in that said axis (7) is located at the proximal ends (5, 6) of the arms (1, 2) , and in that said manual actuation zones (8, 9) are located between said axis (7) and the distal ends (22 to 33) of the arms (1, 2).

2. microsurgical instrument according to claim 1, characterized in that one (2) of the arms (1, 2) has integrally, at its proximal end (6), at least one longitudinal tab (44) arranged in a mean plane (13) perpendicular to said axis (7) while the other arm (1) has integral, at its proximal end (6) at least two longitudinal legs (36, 37) arranged in mean planes respective (38, 39) perpendicular to said axis (7), respectively on either side of the aforementioned longitudinal tab (44), and in that said longitudinal tabs (36, 37, 44) are drilled along said axis (7 ) of respective bores (42, 43, 47) in which is engaged a common pin (48).

3. Microsurgical instrument according to any one of claims 1 and 2, characterized in that it includes means (61, 68, 69 to 75) for limiting mutual spacing of the distal ends (22 to 33) of the arms ( 1, 2).

4. Microsurgical instrument according to claim 3, characterized in that the means (61, 68, 69 to 75) for limiting mutual spacing of the distal ends (22 to 33) of the arms (1, 2) comprise at least two surfaces abutment (69 to 75) respectively integral with the arms (1, 2) and located at said proximal ends (5, 6), approximately transversely, facing one another in a circumferential direction centered on said axis (7) and in a relative position such that they move towards or away from each other when, respectively, said distal ends (22 to 22) move away from or move towards each other.

5. microsurgical instrument according to any one of claims 3 and 4, characterized in that the means (61, 68, 69 to 75) for limiting the distance mutual ment of the distal ends (22 to 33) of the arms (1, 2) comprise at least two abutment surfaces (61, 68) respectively integral with the arms (1, 2) and located between said axis (7) and said distal ends (22 to 33), facing one another in a circumferential direction (67) centered on said axis (7) and in a relative position such that they approach or deviate from each other when, respectively, said said distal ends (22 to 33) move apart or approach each other.

6. Microsurgical instrument according to claim 5, characterized in that said abutment surfaces (61, 68) located between said axis (7) and said distal ends (22 to 33) are closer to said distal ends (22 to 33) than of said axis (7) and approximately longitudinal.

7. microsurgical instrument according to any one of claims 1 to 6, characterized in that it comprises means (40, 41, 45, 46, 62, 63, 65, 66) for mutual guidance of the arms (1, 2 ) relative rotation around said axis (7) without the possibility of relative translation parallel to it.

8. microsurgical instrument according to claim 7, characterized in that the means (40, 41, 45, 46, 62, 63, 65, 66) for mutual guiding of the arms (1, 2) comprise at least two bearing surfaces (40, 41) integral with one of the arms (1) and situated at said proximal end (5) thereof, perpendicular to said axis (7) and in opposite directions, and at least two counterpart surfaces (45 , 46) integral with the other arm (2) and located at said proximal end (6) thereof, perpendicular to said axis (7) and facing, parallel to this axis (7), respectively of one and the other bearing surfaces (41, 42) with which said surfaces counterpart (45, 46) are respectively in contact with the possibility of mutual sliding.

9. microsurgical instrument according to any one of claims 7 and 8, characterized in that the means (40, 41, 45, 46, 62, 63, 65, 66) for mutual guidance of the arms (1, 2) comprise at at least two bearing surfaces (62, 63) integral with one of the arms (1) and located between said axis (7) and said distal ends (22 to 33), perpendicular to said axis (7) and in opposite directions , and at least two counterpart surfaces (65, 66) integral with the other arm (2) and situated between said axis (7) and said distal ends (22 to 33), perpendicular to said axis (7) and facing each other, parallel to this axis (7), respectively of one and the other bearing surfaces (62, 63) with which said counterpart surfaces (65, 66) are respectively in contact with the possibility of mutual sliding.

10. Microsurgical instrument according to claim 9, characterized in that said respectively bearing and counterpart surfaces (62, 63, 65, 66) located between said axis (7) and said distal ends (22 to 33) are closer of said distal ends (22 to 33) than of said axis (7).

11. microsurgical instrument according to any one of claims 9 and 10 in combination with any one of claims 5 and 6, characterized in that the two arms (1, 2) have one towards each other in respective circumferential directions (53, 54) centered on said axis (7), integrally, between said axis (7) and said distal ends (22 to 33), respective transverse projections (49, 50 ) arranged in the same mean plane (13) perpendicular to said axis (7) and offset longitudinally with respect to each other, in that the projection (49, 50) of each arm (1, 2) presents towards the projection (1, 2) of the other arm (1, 2) an approximately longitudinal edge (57, 64) defining on the one hand said abutment surface (61, 68) and on the other hand, respectively said surfaces support or said counterpart surfaces (62, 63, 65, 66).

12. microsurgical instrument according to claim 11, characterized in that each arm (1, 2) has a recess (55, 56) opposite the projection (49, 50) of the other arm (1, 2) in a circumferential direction (53, 54), centered on said axis (7), to freely receive this projection (49, 50).

13. microsurgical instrument according to any one of claims 1 to 12, characterized in that it comprises means (90, 50) of immobilization, at will, of the two arms (1, 2) against a relative rotation around said axis (7) in said second direction, in a relative position of maximum mutual approximation of said distal ends (22 to 33).

14. microsurgical instrument according to claim 13, characterized in that said means (90, 50) for immobilization comprise between said axis (7) and said distal ends (22 to 33), on the one hand a keeper (50) integral one (2) of the arms (2) and on the other hand a lock (90) mounted with longitudinal sliding on the other arm (1) and accessible manually in the zone (8) of manual actuation of this arm (2) to be brought at will in a position of engagement with the keeper (50), to achieve said immobilization, or in a release position with respect to the keeper (50), to remove said immobilization.

15. microsurgical instrument according to claim 14, characterized in that the lock is located between said axis (7) and the keeper (50).

16. microsurgical instrument according to any one of claims 14 and 15 in combination with any one of claims 11 and 12, characterized in that said keeper (50) is constituted by one (50) of said projections (49, 50).

17. microsurgical instrument according to claim 16, characterized in that the latch (90) has, perpendicular to a circumferential direction centered on said axis (7) and towards said projection forming a keeper (50), the shape of a longitudinal fork (100, 101) capable of engaging on either side of said strike projection (50), and in that said strike projection (50) has two flanges (104, 105) located respectively on either side following a direction parallel to said axis (7), for cooperating with the fork (100, 101) in said position of mutual engagement of the latch (90) and the keeper (50).

18. microsurgical instrument according to any one of claims 14 to 17, characterized in that it comprises means (78, 110, 111) of immobi Reading with the bolt (90) against an accidental longitudinal sliding.

19. microsurgical instrument according to any one of claims 1 to 18, characterized in that the means (78) of elastic bias comprise at least one compression spring (78) interposed between the arms (1, 2), between said axis (7) and said distal ends (22 to 33)

20. microsurgical instrument according to claim 19, characterized in that the means (7) of elastic bias comprise at least one leaf spring (78) approximately longitudinal, curved in a mean plane (13) perpendicular to the axis (7) and having two end zones (79, 80) bearing against one of the arms (1) in respective circumferential directions centered on said axis (7) and an intermediate zone (81) bearing against the other arm ( 2) in a circumferential direction centered on said axis (7), between said axis (7) and said distal ends (22 to 33).

21. microsurgical instrument according to claims 18 and 20 in combination, characterized in that the leaf spring (78) is supported by the lock (90) on the arm (1) on which the lock (90) is sliding mounted. longitudinal.

22. microsurgical instrument according to claim 21, characterized in that the latch (90) has towards the spring (78) of the spring a bearing face (83) planar, approximately longitudinal and perpendicular to a centered circumferential direction on said axis (7), said planar bearing face (83) having two depressions (110, 111) capable of receiving the support of the spring (78) respectively in said position of mutual engagement of the latch (90) and of the keeper (50) and in said position of mutual release of the latch (90) and the keeper (50).

23. microsurgical instrument according to any one of claims 20 to 22 in combination with any one of claims 11, 12, 16, 17, characterized in that the spring leaf (78) is located between said axis (7) and said transverse projections (49, 50) of the arms (1, 2).

24. Microsurgical instrument according to any one of claims 1 to 23, characterized in that said distal ends (22 to 29) have the shape of beaks capable of cooperating in a pinching action by mutual contact in a circumferential direction centered on said axis (7) due to a relative rotation of the arms (1, 2) in said first direction (10, 11).

25. microsurgical instrument according to claim 24, characterized in that said nozzles have towards each other in respective circumferential directions centered on said axis (7) of respective claws (121, 122, 125, 126) capable of s 'interpenetrate due to a relative rotation of the arms (1, 2) in said first direction (10, 11).

26. Microsurgical instrument according to any one of claims 1 to 23, characterized in that said distal ends (30 to 33) have the shape of blades capable of cooperating in a cutting action by mutual crossing in a circumferential direction centered on said axis (7) and mutual contact in a direction parallel to said axis (7) due to a relative rotation of the arms (1, 2) in said first direction (10, 11) said blades having for this purpose respective cutting edges (130, 131, 134, 135) antagonistic, oriented in circumferential directions centered on said axis (7).

27. Microsurgical instrument according to any one of claims 1 to 26, characterized in that said distal ends (30, 31) are curved relative to a plane (12) including said axis (7).

28. Microsurgical instrument according to any one of claims 1 to 27, characterized in that said distal ends (22 to 27, 30 to 33) are curved relative to a plane (13) perpendicular to said axis.

29. Microsurgical instrument according to any one of claims 1 to 26, 28, characterized in that said distal ends (22 to 29, 32, 33) are arranged along a plane (12) including said axis (7).

30. Microsurgical instrument according to any one of claims 1 to 27, 29, characterized in that said distal ends (28, 29) are arranged in a plane (13) perpendicular to said axis (7).