Surgical instrument, tool arrangement for such a surgical instrument, and method for manufacturing such a tool arrangement

Abstract

The present application relates to a surgical instrument, a tool arrangement for such a surgical instrument, and a method for manufacturing such a tool arrangement. A surgical instrument is known that comprises a shaft, a tool arrangement having a first jaw portion, a second jaw portion, and a control assembly, and a handle arrangement. According to the present application, the second jaw portion comprises a receiving recess with a control protrusion of the control assembly. For use in a surgical instrument.

Description

[Technical field]

[0001] The present application relates to a surgical instrument comprising a shaft extending along a shaft longitudinal axis, a tool arrangement disposed distally of the shaft and having a first jaw portion and a second jaw portion, the first jaw portion and the second jaw portion being pivotable relative to one another about a pivot axis oriented transversely to the shaft longitudinal axis to form an openable and closable tool port, and a gripping device disposed proximally of the shaft and having an operating element operably connected to the tool arrangement via a push-pull element, the operation of which causes the push-pull element to move longitudinally. and a gripping device translatable along an axis, the tool device having a control structure with a control pin and at least one control groove, the at least one control groove formed in a control portion of the first jaw portion, the control pin extending parallel to the pivot axis and axially engaged through the at least one control groove, the control pin slidable along the control groove between a proximal end position of the control pin and a distal end position of the control pin by longitudinal movement of a push-pull element, thus applying a torque acting about the pivot axis to the first jaw portion to open and close the tool port. [Background technology]

[0002] A surgical instrument of this kind is known from US patent application 2020 / 0179038 and is provided in the form of an endoscopic forceps instrument for sealing and / or cutting body tissue. The known surgical instrument has an elongated instrument shaft, a gripping device with an operating element and a tool arrangement with an openable and closable tool mouth. The tool arrangement is arranged at the distal end of the instrument shaft. The gripping device is arranged at the proximal end of the instrument shaft. The operating element is operably connected to the tool arrangement via a push-pull element, which extends longitudinally in the instrument shaft and is movable in translation to open and / or close the tool mouth. For this purpose, the push-pull element engages with a control pin of a control structure of the tool arrangement. The control structure of such a known surgical instrument has a first control groove formed in the first jaw part and a second control groove formed in the second jaw part. A control pin engages through both control grooves and is slidable along the control grooves between proximal and distal end positions of the control pin by longitudinal movement of the push-pull element, which in this way translates into pivoting of the two jaws about the pivot axis for opening and / or closing of the tool port. Summary of the Invention [Problem to be solved by the invention]

[0003] It is an object of the present application to make available a surgical instrument of the type mentioned in the introduction, a tool arrangement for such an instrument, and a method for such a tool arrangement, each of which offers advantages over the prior art. In particular, it is an object of the present application to enable a simplified design of the surgical instrument and / or the tool arrangement, and in this connection an easy manufacture. [Means for solving the problem]

[0004] With respect to the surgical instrument, this object is achieved by the fact that the second jaw part has a receiving recess for at least partially receiving the control part of the first jaw part, with at least one control projection projecting inwardly from the inner wall of the receiving recess in the axial direction of the control pin and forming the control surface of the control structure, the control pin sliding along and being supported radially on the control projection in the movement between the proximal and distal end positions of the pin. The solution according to the present application makes it possible to dispense with a control groove arranged and / or formed in the second jaw part. Such a control groove is usually manufactured as an oblong hole by milling, which is rather complicated. Instead of a conventional control groove, the second jaw part has at least one control projection projecting inwardly from the inner wall of the receiving recess in the axial direction of the control pin and forming the control surface of the control structure. In this way, a relatively simple design and simple manufacture of the tool device and, consequently, of the surgical instrument is possible. The surgical instrument is preferably provided for grasping, holding, clamping, sealing and / or cutting body tissue in minimally invasive surgery, in particular laparoscopic surgery. The tool device is therefore preferably designed in the form of a forceps, clamp and / or scissors, with the first and second jaws forming the mouth of the forceps, clamp and / or scissors. The jaws can also be designated as instrument branches or tissue branches. The first and second jaws are pivotable relative to each other about a pivot axis so that a pressure can be exerted as intended on the body tissue located between the first and second jaws. For this purpose, both jaws can be pivotable relative to the pivot axis. Alternatively, the first jaw can be pivotable and the second jaw fixed, or vice versa. The control structure serves to convert a translational movement of the push-pull element directed along a longitudinal movement axis into a pivotal movement of the first jaw portion and / or the second jaw portion about a pivot axis. The longitudinal movement axis is preferably oriented parallel to the shaft longitudinal axis. The pivot axis is preferably oriented perpendicular to the longitudinal movement axis and / or the shaft longitudinal axis.The control groove of the first jaw part is preferably inclined with respect to the longitudinal movement axis. If the first jaw part is pivotable about a pivot axis, the corresponding inclination angle of the control groove can vary depending on the pivot position of the first jaw part with respect to the longitudinal movement axis. The control surface formed by at least one control protrusion of the second jaw part can be parallel and / or at least partially inclined with respect to the longitudinal movement axis. The second jaw part preferably has a control protrusion arranged on both sides of the receiving recess in the axial direction of the control pin. The second jaw part can also be designed as one piece or divided into several parts. In that case, the second jaw part preferably has an active part arranged to act on the body tissue and a housing part carrying the receiving recess with at least one control protrusion, the active part and the housing part being each manufactured separately and then preferably connected to each other in a mold-fitting manner.

[0005] In one embodiment of the present application, the second jaw part has a fixing surface which defines a receiving recess in the axial direction of the control pin and which positively fixes the control pin against axial displacement in the movement between the proximal and distal end positions of the control pin. In this way, it is possible to dispense with a separate force-fit and / or adhesive bond connection of the control pin to the push-pull element for axial fixation. This leads to a simpler design and further to a simpler manufacture. The fixing surface is formed on the inner wall of the receiving recess. In this embodiment of the present application, the receiving recess is closed on both sides in the axial direction of the control pin. In the movement between the proximal and distal end positions of the pin, the control pin moves in the receiving recess along the control projection and between the fixing surfaces which are opposite to its axial direction.

[0006] In a further embodiment of the present application, the second jaw part has a pivot bearing surface which forms the pivot axis and which slides and interacts with a complementary pivot bearing surface of the first jaw part. In this way, it is possible to dispense with a separate component for forming a pin or bolt connection between the first and second jaw parts which is pivotable about the pivot axis. The reduction in the number of such components allows a simplified design and, in this connection, an advantageous manufacture of the tool device and / or surgical instrument. The pivot bearing surface of the second jaw part and the complementary pivot bearing surface of the first jaw part slide about the pivot axis and positively interact radially at least to one side, preferably radially inwards, relative to the pivot axis. The pivot bearing surface of the second jaw part is preferably convex and the complementary pivot bearing surface of the first jaw part is preferably matching concave, or vice versa.

[0007] In a further embodiment of the present application, the pivot bearing surface of the second jaw part is formed by the outer periphery of a transverse web part which extends in the axial direction of the control pin above the receiving recess. The transverse web part creates an adhesive bond connection and / or an integral connection between the inner walls of the receiving recess which are oriented oppositely in the axial direction of the control pin. The transverse web part can also be designated as a bridge. The transverse web part extends parallel to the pivot axis. The pivot bearing surface of the second jaw part is preferably formed by the lower surface of the transverse web part or alternatively by its upper surface.

[0008] In a further embodiment of the present application, the second jaw part has a pivot guideway curved concentrically with respect to the pivot axis, which slides and interacts with a complementary pivot guideway of the first jaw part. The pivot guideway of the first jaw part and the complementary pivot guideway of the second jaw part interact in a form-fitting manner so as to be radially slidable about the pivot axis. The pivot guideway and the complementary pivot guideway serve to improve the pivotal guidance of the tool mouth about the pivot axis. If the pivot axis is arranged in an upper region of the second jaw part relative to the vertical direction, the pivot axis guideway is preferably arranged in a lower region of the second jaw part, or vice versa. Due to the pivot guideway formed between the pivot guideway and the complementary pivot guideway, it is possible to dispense with separate associated parts and thus achieve a further simplified design. In other words, the pivot guideway is formed directly between the first jaw part and the second jaw part.

[0009] In a further embodiment of the present application, the second jaw part has a longitudinal guide surface extending parallel to the longitudinal movement axis of the push-pull element, which at least temporarily slidably guides the complementary longitudinal guide surface of the push-pull element during its longitudinal movement. The longitudinal guide between the second jaw part and the push-pull element counteracts unwanted movements of the push-pull element directed transversely to the longitudinal movement axis. At the same time, this also avoids unwanted movements of the control pin acting on the push-pull element. This assists the intended movement of the control pin along at least one control projection. In particular, unwanted lifting of the control pin from the control surface formed by the control projection can be counteracted. The longitudinal guide surface is preferably arranged in the proximal region of the second jaw part. The complementary longitudinal guide surface is preferably formed by the upper or lower side of the push-pull element. The slidable guide between the second jaw part and the push-pull element preferably only temporarily acts, for example when the control pin moves in the region of its proximal end position.

[0010] In a further embodiment of the present application, a stop arranged and / or formed on the second jaw part positively interacts with a complementary stop on the first jaw part about the pivot axis in the open position of the tool mouth. This prevents the tool mouth from opening beyond the open position. The complementary stop on the first jaw part is preferably arranged close to its control part. The stop assigned to the second jaw part is preferably arranged and / or formed in the region of the receiving recess. This stop is particularly preferably a wall of the connecting sleeve which can be pressed against the proximal end of the second jaw part.

[0011] In a further embodiment of the present application, the second jaw portion is fixed relative to the pivot axis and the first jaw portion rotates relative to the second jaw portion about the pivot axis during opening and closing of the tool mouth. In this context, this is also referred to as one-sided pivoting of the tool mouth. This is in contrast to bilateral pivoting, where both jaw portions rotate about the pivot axis to open and close the tool mouth. The embodiment with one-sided pivoting allows for a further simplified design of the tool arrangement.

[0012] In a further embodiment of the present application, the second jaw part has a housing part consisting of one piece and an active part attached to the distal side of the housing part, the housing part having at least a receiving recess with at least one control projection and / or pivot bearing surface. The active part is preferably attached in a form-fitting manner to the housing part. The active part can be mounted in the housing part rigidly or tiltably about a tilt axis, which preferably runs parallel to the pivot axis. When provided in this way, the pivot bearing surface, the pivot guide surface, the longitudinal guide surface and / or the stop are preferably also formed in the housing part. This kind of one-piece design offers many advantages in terms of manufacturing and assembly.

[0013] In a further embodiment of the present application, the control groove extends continuously and linearly between the proximal and distal groove ends, which may result in more simplified manufacture compared to longitudinally angled, partially linear control grooves.

[0014] In a further embodiment of the present application, the control surface has a proximal surface portion and a distal surface portion, which are inclined differently with respect to the longitudinal movement axis in such a way that different transmission ratios are realized between the longitudinal movement of the push-pull element and the pivoting of the tool mouth in the movement of the control pin between the proximal and distal end positions of the control pin. Correspondingly, the longitudinal force associated with the longitudinal movement and the clamping force associated with the pivoting of the tool mouth necessarily have different transmission ratios, which can be exerted on the body tissue located between the jaws. The different inclined surface portions of the control surface allow a relatively fast initial closing of the tool mouth, starting from the opening position of the tool mouth, and a relatively slower closing of the tool mouth thereafter. In this way, the initial opening of the tool mouth can be realized with a relatively small longitudinal movement of the push-pull element and thus with a small manual operating path of the operating element. In other words, the stroke required for the operating element can be reduced, which is particularly advantageous for people with small hands. At the same time, a relatively large clamping force can be generated at the tool mouth using a relatively small manual operating force on the operating element. Variable transmission in the sense of this embodiment can also be achieved by means of a non-linear oval hole, i.e. an oval hole with different inclinations in the length direction.

[0015] In a further embodiment of the present application, the proximal surface extends parallel and / or at least substantially parallel to the longitudinal movement axis. This results in a relatively small transmission ratio in this embodiment of the present application when the control pin moves along the proximal surface. Thus, a relatively small manual operating force on the operating element causes a relatively large clamping force at the tool mouth. The control pin is preferably located in the area of ​​the proximal surface at its proximal end position.

[0016] In a further embodiment of the present application, the distal surface is curved concentrically with respect to the pivot axis. Depending on the direction of movement of the control pin, different advantages are realized as a result. In the movement towards the proximal end position of the pin, the control pin always has a constant lever arm with respect to the pivot axis when moving along the distal surface. This ensures a constant transmission ratio in the area of ​​the distal surface. This can lead to advantages in terms of ease of application and user friendliness. During the movement towards the distal end position of the pin, the curved concentric longitudinal outer edge of the distal surface preferably ensures a constant radial play between the control pin and the distal surface during pivoting. This leads to further advantages, since in the reversal of the movement initiated by the operator, the operator can always expect a constant play, i.e. a constant idle stroke on the operating element. This further improves the ease of application and user friendliness.

[0017] In a further embodiment of the present application, the distal surface is linear and tangent to a circular arc arranged concentrically with respect to the pivot axis, which, compared to the previous embodiments of the present application, allows for simplified manufacture of the distal surface while providing the same ease of application and user friendliness.

[0018] In a further embodiment of the present application, the control pin is at least temporarily held in the distal groove end of the control groove and rotates together with the first jaw part about the pivot axis in the movement towards the distal end position of the control pin, in this way it is possible to counteract excessive radial play between the control pin and the control surface of the control projection, in particular the distal surface part of the control surface.

[0019] The present application also relates to a tool arrangement for a surgical instrument according to the above description, having first and second jaw portions pivotable relative to one another about a pivot axis to form an openable and closable tool port, the tool arrangement having a control structure with a control pin and at least one control groove, the at least one control groove being formed in a control portion of the first jaw portion, the control pin extending parallel to the pivot axis and axially engaged through the at least one control groove, the control pin being slidable along the control groove between a proximal end position of the control pin and a distal end position of the control pin, thus applying a torque acting about the pivot axis to the first jaw portion to open and close the tool port.

[0020] With regard to the tool arrangement, the object mentioned at the outset is achieved by the fact that the second jaw part has a receiving recess for at least partially receiving the control part of the first jaw part, at least one control projection protruding inwards from the inner wall of the receiving recess in the axial direction of the control pin and forming a control surface of the control structure, the control pin sliding along and being supported radially on the control projection in the movement between the proximal and distal end positions of the pin. With regard to the advantages related to the tool arrangement according to the present application, explicit reference is made to the above description in order to avoid repetition. What has been said with regard to the tool arrangement of the surgical instrument according to the present application also applies in the same way with regard to the tool arrangement according to the present application. Advantageous embodiments of the tool arrangement according to the present application will be clearly evident from the features of the tool arrangement of the embodiments of the surgical instrument according to the present application.

[0021] The present application further relates to a method for manufacturing a tool arrangement according to the above description. The method comprises a step of primary moulding of a second jaw part, whereby at least one housing part of the second jaw part carrying at least one control projection is provided by primary moulding. The primary moulding is preferably carried out by powder injection moulding (metal injection moulding). The design of the second jaw part according to the present application allows the use of a primary moulding tool with a relatively simply designed. In particular slides, stamps etc. can be dispensed with in the primary moulding tool.

[0022] In a further embodiment of the present application, the method includes a step of positively joining together the first jaw part and the molded housing part, where a pivot bearing surface of the second jaw part formed in the housing part and a complementary pivot bearing surface of the first jaw part form a pivot axis and are slidable about the pivot axis and are fixed to each other in a form-fitting manner in a radial direction relative to the pivot axis. Thus, to form the pivotability of the tool mouth, the first jaw part and the second jaw part are not connected to each other, for example, by a separate pin, shaft or bolt element. Rather, the first jaw part and the second jaw part are joined in a form-fitting manner so as to be directly slidable about the pivot axis in a radial direction thereof. This joint connection is formed between the pivot bearing surface of the second jaw part and the complementary pivot bearing surface of the first jaw part.

[0023] Further advantages and features of the present application will become apparent from the following description of preferred exemplary embodiments of the present application, as illustrated in the claims and the drawings. [Brief description of the drawings]

[0024] [Figure 1] 1 is a schematic side view of an embodiment of a surgical instrument according to the present application having a gripping device and an elongated shaft, and an embodiment of a tool device according to the present application. [Diagram 2] FIG. 2 is an exploded perspective view showing a tool arrangement having a first jaw portion and a multi-piece second jaw portion, as well as further components of the surgical instrument. [Diagram 3] 5 shows a housing part assigned to the second jaw part along the section III-III according to FIG. 4; FIG. [Figure 4] FIG. 4 is a plan view of the housing part according to FIG. [Diagram 5] 5A and 5B show a modification of the housing part according to FIGS. 3 and 4; [Figure 6] FIG. 4 is a schematic side view of a first jaw portion. [Figure 7]FIG. 7 is a plan view of the first jaw part according to FIG. 6; [Figure 8] FIG. 14 is a schematic plan view of the tool arrangement, including stepwise section IX-IX associated with FIGS. 9 to 13. [Figure 9] 2 is a cross-sectional view of the tool arrangement with the tool mouth formed by the first and second jaw portions in an open position; FIG. [Figure 10] 13 is a further cross-sectional view of the tool apparatus with the tool mouth being moved from an open position towards a closed position; FIG. [Figure 11] 4 is a further cross-sectional view of the tool apparatus, with the tool port in a closed position; FIG. [Figure 12] 13 is a further cross-sectional view of the tool apparatus while the tool mouth is closed and moving towards an open position; FIG. [Figure 13] FIG. 2 is a further cross-sectional view in the functional position further towards the open position. [Figure 14] FIG. 2 is a schematic diagram showing a plot of the tool mouth opening angle over the operating path of an operating element of the gripping device. [Figure 15] 5A-5C are schematic diagrams illustrating method steps for manufacturing a tool arrangement; [Figure 16] FIG. 4 is a further schematic diagram showing further method steps. [Figure 17] FIG. 4 is a further schematic diagram showing further method steps. [Figure 18] FIG. 4 is a further schematic diagram showing further method steps. [Figure 19] 11A-11C are further schematic diagrams illustrating further method steps relating to mounting a tool arrangement at a fixed angle on a shaft. [Figure 20] 4A-4C are further schematic diagrams illustrating further method steps relating to the articulated mounting of the tool device on a shaft. [Figure 21] 4A-4C are further schematic diagrams illustrating further method steps relating to the articulated mounting of the tool device on a shaft. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] According to FIG. 1, the surgical instrument 1 has a shaft 2 extending longitudinally along a shaft longitudinal axis L, a tool device 3 arranged distally of the shaft 2, and a grip device 4 arranged proximally of the shaft 2.

[0026] The tool arrangement 3 has a first jaw portion 5 and a second jaw portion 6. The two jaw portions 5, 6 are oriented transversely to the shaft longitudinal axis L and are pivotable relative to each other about a pivot axis S (FIG. 2) to form an openable and closable tool mouth M.

[0027] In the illustrated embodiment, the second jaw portion 6 is of a several-piece design and comprises a proximal housing portion 7 and a distal active portion 8 which is positively fixed to the distal end of the housing portion 7 in a manner which will be described in more detail below. Such a multiple-piece design of the second jaw portion 6 is advantageous but is not considered essential in view of the teachings of the present application. Therefore, in the embodiment not shown, the second jaw portion is of a one-piece design.

[0028] The gripping device 4 has a manually operable operating element 9 operably connected to the tool device 3 via a push-pull element 10 such that the tool mouth M can be opened and / or closed by operation of the operating element 9 in order to grasp and clamp body tissue located between the jaws 5, 6.

[0029] The design of the gripping device 4 shown in FIG. 1 should be considered purely as an example. In this example, the gripping device 4 has a housing formed from a number of housing parts (not specified in more detail) and on which and / or in which further components of the gripping device, in particular the operating element 9, are mounted. In FIG. 1 only one housing half of said housing (not specified in more detail) is shown. For the movable mounting of the operating element 9 on the housing, the gripping device 4 has an operating mechanism 41, the design of which is known in principle and is described, for example, in German patent application No. 10 2017 109 891. Furthermore, a coupling mechanism 42 is provided, which is likewise described in the aforementioned patent application and serves to couple the operating element 9 to the push-pull element 10 in a force- and movement-transmitting manner. The operating element 9, which is not shown in more detail in the figures, can be manually moved in a reciprocating manner relative to the housing of the gripping device 4 between a distal end position (FIG. 1) and a proximal end position. The operating element 9 can be locked in the proximal end position in a manner known per se by a locking mechanism 43, also called a rotation lock. The operating mechanism 41 can have a spring element, not specified in more detail, to assist the movement of the operating element 9 in the direction of the distal end position.

[0030] The push-pull element 10 is translatable along a longitudinal movement axis L' by the aforementioned reciprocating movement of the operating element 9. In the illustrated embodiment, the longitudinal movement axis L' of the push-pull element 10 coincides with the shaft longitudinal axis L. At its distal end, the push-pull element 10 is operably connected to a control structure 11 of the tool arrangement 3 in a manner described in detail below. The control structure 11 is configured to convert a translational movement of the push-pull element 10 into a pivoting movement of the first jaw part 5 and / or the second jaw part 6 about the pivot axis S.

[0031] In the illustrated embodiment, the second jaw portion 6 is fixed relative to the pivot axis S, and the first jaw portion 5 is pivotable relative to the pivot axis S. In this sense, only the first jaw portion 5 is pivoted to open and close the tool mouth M. In this context, it is also referred to as one-sided pivotability. This is in contrast to bilateral pivotability, where both jaw portions are pivotable relative to the pivot axis S. In embodiments not shown in the drawings, such bilateral pivotability can be provided.

[0032] In the embodiment shown in Fig. 1, the entire tool arrangement 3 is fixed to the shaft 2 so that it can be bent about the shaft longitudinal axis L. A bending mechanism 12, 13 with an operating unit 12 on the grip side and a swivel unit 13 on the shaft side is provided for bending the tool arrangement 3. The structure and function of the bending mechanisms 12, 13 are known in principle and are described, for example, in EP Patent No. 2 688 501. Alternatively, the tool arrangement 3 can also be fixed to the shaft 2 rigidly and / or only rotatably about the shaft longitudinal axis L.

[0033] In the present embodiment, the push-pull element 10 is strip-shaped and extends longitudinally in the shaft 2 (FIG. 2). In order to improve the longitudinal guidance of the push-pull element 10, especially in the shaft 2, a guide element 21 is arranged in the shaft in this example.

[0034] At its proximal end, the push-pull element 10 interacts with a component 421 of the linkage mechanism 42. At its distal end, the push-pull element 10 interacts with a control pin 14 of the control structure 11.

[0035] The control structure 11 has at least one control groove 51 (FIG. 6) and at least one control protrusion 71. The at least one control groove 51 is assigned to the first jaw part 5. The at least one control protrusion 71 is assigned to the second jaw part 6, which in this example is formed on its housing part 7. In the translational movement of the push-pull element 10, the control pin 14 slidingly interacts with the control groove 51 and the control protrusion 71. Before considering further functions of the control structure 11 in opening and closing the tool mouth 12, further features of the first jaw part 5 and the second jaw part 6 are explained with reference to FIGS. 3 to 7.

[0036] As shown in particular in Figures 3 and 4, the second jaw part 6 has, in this example, in its housing part 7, a receiving recess 72. At least one control projection 71 projects inwardly from an inner wall 73 of the receiving recess 72 in the axial direction A (Figure 2) of the control pin 14. The at least one control projection 71 forms a control surface 74 of the control structure 11, which control surface 74 interacts with the control pin 14 in a manner that will be described in more detail below. In the illustrated embodiment, the control surface 74 extends at partially different inclination angles relative to the shaft longitudinal axis L and / or the longitudinal movement axis L' in a manner that will be described in more detail below. In non-illustrated embodiments, the control surface can instead extend continuously parallel or inclined relative to the aforementioned longitudinal axis.

[0037] The second jaw part 6, and in particular its housing part 7, has in this example a mirror-symmetrical design (FIG. 4). Thus, in the axial direction A of the control pin 14, a further control projection 71' is provided, which projects inwards from the inner wall 73' of the recess 72. This further control projection 71' forms a further control surface 74'. During its movement, the control pin 14 interacts in a sliding manner with both control projections 71, 71' and with the control surfaces 74, 74' formed thereon. For details of the control projections 71 and their control surfaces 74, 74', reference is made to the first embodiment in order to avoid repetition. What has been disclosed in that connection applies accordingly to the control projections 71' and the control surfaces 74' thereof. The same applies in the other ways.

[0038] The housing part 7 extends between a proximal end and a distal end along its longitudinal axis L1. In the illustrated embodiment, the receiving recess 72 is located approximately in the middle between the proximal and distal ends of the housing part 7 and is open distally with respect to the longitudinal axis L1 and at the top with respect to the drawing plane of FIG. 3. In the ready-to-operate state, the proximal end of the housing part 7 is mold-fittedly fixed to the distal end of the shaft 2 (FIG. 2). The active part 8 is located at the proximal end of the housing part 7 and is mold-fittedly attached to the receiving part 75 of the housing part 7 so as to be tiltable along the longitudinal axis L1 about the tilt axis K (FIG. 2). The active part 8 is provided to act on body tissue and, in an embodiment not shown, is rigidly attached to the housing part 7. In a further embodiment, the active part 8 can be formed as one piece together with the housing part 7.

[0039] In the assembled state ready for operation, the control pin 14 is located in the receiving recess 72. The control pin 14 is held in a form-fitting manner in the axial direction A between the inner walls 73, 73', which here form fixing surfaces 76, 76' for axially fixing the control pin 14. The two inner walls 73, 73', and thus the two fixing surfaces 76, 76', are spaced apart from one another in the axial direction A by a distance that is slightly greater than the axial length of the control pin 14.

[0040] In this example, the second jaw part 6, or more precisely its housing part 7, has a pivot bearing surface 77 which interacts with a complementary pivot bearing surface 52 (FIG. 6) of the first jaw part 5 while forming a pivot axis S. In this example, the pivot bearing surface 77 is formed by the outer periphery of a transverse web part 78 which extends in the axial direction A of the control pin 14 above the receiving recess 72. The transverse web part 78 can also be called a bridge. The pivot bearing surface 77 is formed by the underside of the transverse web part 78 with respect to the drawing plane of FIG. 3. The pivot axis S is located above the control surface 74. In the assembled state ready for operation, the control part 53 of the first jaw part (FIG. 6), which carries the control groove 51, engages under the transverse web part 78, and the complementary pivot bearing surface 52, which is pivotable about the pivot axis S, is supported radially inwardly in a form-fitting manner on the pivot bearing surface 77.

[0041] Furthermore, in this example, the second jaw part 6, more precisely its housing part 7, has a pivot guideway 79, which in this example is located at the distal end of the receiving recess 72. In this case, the pivot guideway 79 runs concentrically and curved with respect to the pivot axis S. In the assembled state ready for operation, the pivot guideway 79 interacts in a form-fitting manner with a complementary pivot guideway 54 (FIG. 6) of the first jaw part, slidably about the pivot axis S and radially outwardly with respect to the pivot axis S. Here, a further pivot guideway 79' is provided. The two pivot guideways 79, 79' of the housing part 7 are arranged and / or designed mirror-symmetrically with respect to its longitudinal axis L1. The further pivot guideway 79' interacts in a corresponding manner with a further complementary pivot guideway of the first jaw part 5, not shown in detail. In embodiments not shown in the drawings, only one pivot guide surface and one complementary pivot guide surface are provided.

[0042] In this example, the second jaw part 6 has a longitudinal guide surface 80 in its housing part 7. The longitudinal guide surface 80 extends parallel to the longitudinal movement axis L' of the push-pull element 10 and serves to support the push-pull element 10 vertically on one side. For this purpose, the longitudinal guide surface 80 interacts in a form-fitting manner at one end with a complementary longitudinal guide surface 101 of the push-pull element 10 which slides along the longitudinal movement axis L' and in a vertical direction perpendicular to the longitudinal movement axis L'. In this example, the complementary longitudinal guide surface 101 is formed by the upper flat side surface of the push-pull element. In this example, the slidable support of the push-pull element 10 is only temporarily and is enabled by the respective displacement state of the control pin 14 along the control surface 74. This will be considered in more detail below. The longitudinal guide surface 80 is arranged at the proximal end of the housing part 7.

[0043] In the illustrated embodiment, the control surface 74 has a proximal surface portion 741 and a distal surface portion 742. The two surfaces 741, 742 extend at different inclinations relative to the longitudinal axis L1 and thus relative to the shaft longitudinal axis L and / or the longitudinal movement axis L' aligned parallel thereto. The proximal surface portion 741 extends parallel to the longitudinal movement axis L'. The distal surface portion 742, on the other hand, extends at an inclination. The inclination of the distal surface portion 742 is in the distal direction from top to bottom (FIG. 3). The distal surface portion 742 is straight and oriented tangent to a circular arc arranged concentrically with respect to the pivot axis S.

[0044] A variant with a different configuration of the distal face 742a is shown in Fig. 5, which depicts only the symmetrically opposed faces 741' and 742'a. In contrast to the distal face 742 of the variant according to Figs. 3 and 4, the distal face 742a is curved and extends concentrically with respect to the pivot axis S. The variant shown in Fig. 5 is identical to the embodiment shown in Figs. 3 and 4, apart from the design of the distal face 742a. ​​In this example, the distal face 742a is spaced apart from the pivot axis S by a radius R.

[0045] Compared to the curved distal surface 742a, the straight distal surface 742 is relatively easy to manufacture. In contrast, the curved design of the distal surface 742a offers advantages that will be explained in more detail below, in particular with regard to guiding the control pin 14 with as little play as possible.

[0046] The first jaw part 5 extends along a longitudinal axis L2 between a distal end and a proximal end. A control part 53 carrying a control groove 51 is arranged on the proximal side. Like the second jaw part 6, the first jaw part 5 has an active part 55 arranged on the distal side. In contrast to the active part 8 of the second jaw part 6, the active part 55 is integrated with the rest of the first jaw part 5. In other words, the first jaw part 5 is made of one piece as a whole, although this is not absolutely necessary. In the first jaw part 5, for example, electrodes and insulating components for sealing against body tissue can also be arranged. In the illustrated embodiment, the control part 53 has, in addition to the control groove 51, a complementary pivot bearing surface 52 and a complementary pivot guide surface 54. The complementary pivot bearing surface 52 is arranged on the upper side (with respect to the drawing plane of FIG. 6) of the control part 53. The complementary pivot guide surface 54 is arranged on the lower surface 54. The control groove 51 extends between a proximal groove end 511 and a distal groove end 512. In the present example, the control groove 51 between the groove ends 511, 512 is continuously linear and is not, for example, angled or curved. It may be provided in embodiments not shown in the drawings. The control groove 51 extends at an angle to the longitudinal axis L2 of the first jaw part 5. The longitudinal inclination here is from the bottom towards the distal upwards. In either case, in the closed position of the tool mouth M (FIG. 11), the longitudinal axis L2 of the first jaw part 5 is oriented parallel to the longitudinal axis L1 of the second jaw part 6 and thus also parallel to the shaft longitudinal axis L and / or the longitudinal movement axis L'. In the closed position, the control groove 51 is inclined at an angle α (FIG. 6) to the aforementioned longitudinal axes L, L', L1, L2. The inclination angle α is of course invariant to the pivot position of the first jaw part 5 about the pivot axis S with respect to the longitudinal axis L2. In contrast, the inclination angle α also varies with respect to the longitudinal axes L, L', L1 with the pivot position.

[0047] In this example, the first jaw part 5 also has a stop 56 which interacts with a complementary stop 151 (FIG. 17) assigned to the second jaw part 6 in order to limit the open position. The complementary stop 151 is arranged on the sleeve 15 in the illustrated embodiment. In an embodiment not shown in the drawings, the complementary stop part can instead be formed directly on the housing part. In the illustrated embodiment, the stop 56 projects proximally in the form of a pin from the control part 53.

[0048] As shown in Fig. 7, the first jaw part 5 in the illustrated embodiment has a mirror-symmetrical design with respect to its longitudinal axis L2. The control part 53 has a receiving slot 57 which runs parallel to the longitudinal axis L2 and is provided for receiving the distal end of the push-pull element 10. The receiving slot 57 subdivides the control part 53 and the functional surfaces and / or parts arranged thereon into sub-surfaces and / or sub-parts arranged and designed with mirror symmetry. In this sense, for example, one can refer to a control groove 51 and a further control groove separated by the receiving slot 57. However, for the sake of simplicity, only the control groove 51 will be referred to below.

[0049] The control pin 14, radially fixed in a bore 102 (fig. 2) on the push-pull element 10, projects in the assembled state ready for operation through the control groove 51 in the axial direction A. At its end projecting axially from the control groove 51, the control pin 14 radially interacts with a control surface 74, 74' (fig. 4). In the context of the following functional description with reference to figures 8 to 13, for the sake of simplicity, only the control surface 74 or the control projection 71 will be considered.

[0050] Figure 9 shows the open position of the tool mouth M. In this position, the first jaw part 5 is pivoted relative to the second jaw part 6 by an angle (not specified) about the pivot axis S, so that body tissue can be grasped between the two jaw parts 5, 6, more precisely between the active parts 8, 55. In the open position of the tool mouth M, the control pin 14 is in the distal pin end position. The operating element 9 is in the position shown in Figure 1. The push-pull element 10 is moved along the longitudinal movement axis L' to the distal end position.

[0051] To move the tool mouth M in the direction of the closed position (FIG. 11), the operating element 9 is manually moved in the proximal direction with a pivot and / or stroke movement. The operating mechanism 41 and the coupling mechanism 12 convert the proximal stroke movement of the operating element 9 into a proximal longitudinal movement of the push-pull element 10 in a manner basically known. In this way, the control pin 14 shifts relative to the control groove 51 and the control surface 74 (FIG. 9) starting from the distal end position of the pin. In this example, in the distal end position, the control pin 14 is located in the region of the distal end of the distal surface portion 742a and at the same time in the region of the distal groove end 512. From there, the control pin 14 moves proximally along the distal surface portion 742a and applies a torque about the pivot axis S to the first jaw part 5. The control pin 14 is displaced proximally and at the same time vertically upwards with respect to the drawing plane of FIGS. 9 to 13 due to the existing longitudinal inclination of the distal surface portion 742a. In addition to the translational movement, the push-pull element 10 here also performs a slight rotation about a pivot axis (not specified in detail, oriented parallel to the pivot axis S) in the region of the linkage 42. The distal face 742a is curved concentrically with a radius R about the pivot axis S, so that the control pin 14 is guided here on a circular path of radius R about the pivot axis S.

[0052] In the case of the linear angled guide path according to FIGS. 3 and 4, the control pin 14 does not follow the circular path described above, but is instead guided linearly along the distal face 742 .

[0053] In the functional position shown in FIG. 10, the control pin 14 has shifted beyond the distal face 742a to the proximal face 741. The tool mouth M is not yet completely closed, but instead is open by an opening width a. In this functional position, preferably, no clamping force, or at least no significant clamping force, is exerted on the body tissue located between the jaws 5, 6. Rather, the clamping force is increased starting from the functional position shown in FIG. 10. For a complete closure of the tool mouth M and the associated increase in clamping force, the control pin 14 moves further proximally starting from the position shown in FIG. 10. Here, the control pin 14 slides along the proximal face 741 oriented parallel to the longitudinal movement axis L'. At the same time, further vertical movement of the push-pull element 10 is prevented by the longitudinal guide surface 80.

[0054] The closed position of the tool mouth M is shown in Fig. 11. In this position, an additional increase in the clamping force can be achieved by further proximal movement of the control pin 14. The parallel orientation of the proximal face 741 and its positioning relative to the pivot axis S results in a particularly advantageous lever ratio for transmitting forces and / or torques to the first jaw 5. The general lever ratio can be described by the lever arms b, c in the functional position shown in Fig. 11.

[0055] Starting from the closed position (FIG. 11), the operating element 9 is moved distally in a stroke or pivot movement, if necessary after the rotation lock 43 has been released beforehand, in order to open the tool mouth M. The push-pull element 10 thus moves distally along the longitudinal movement axis L'. The control pin moves distally along the proximal face 741 (FIG. 12).

[0056] A further functional position when opening the tool mouth M is shown in Fig. 13. In this position, the control pin 14 has moved further in the distal direction and is located at the transition between the proximal face 741 and the distal face 742a. ​​At the same time, in this functional position, the control pin 14 is held in the distal groove end 512 of the control groove 51. As a result, excessive radial play is prevented with respect to the distal face 742a during further movement of the control pin 14.

[0057] FIG. 14 shows the relationship between the opening angle of the tool mouth M and the translational movement of the push-pull element 10. It can also be called the stroke and is shown on the horizontal axis. The unspecified opening angle of the tool mouth M is shown on the vertical axis. The curve K1 shows the course of the opening angle over the stroke of the design described in particular with reference to FIGS. 9 to 13. The curve K1 can be approximately divided into two linearly extending curved sections K11, K12. In the present example, the origin of the coordinates corresponds to the distal end position of the pin and therefore to the open position of the tool mouth M (FIG. 9). The course of the curve can be subdivided into two regions B1, B2.

[0058] Starting from the distal end position of the pin, the opening angle initially has a relatively steep slope over the stroke (curved portion K11). Here, the control pin 14 moves along the distal face 742a. ​​In this example, the transition between the distal face 742a and the proximal face 741 is at about 2 mm of stroke. With further increase in stroke, the control pin 14 enters the proximal face 741. The profile of the opening angle then becomes noticeably flatter (curved portion K12).

[0059] This means that a relatively large reduction in the opening angle is first realized at a relatively small stroke (region B1). This is the region where the applied forces are small (no increase in clamping force) so that the reduction in the stroke does not have a negative effect on the operating force required of the operating element 9. At the transition to region B2, the change in stroke remains the same but the change in the opening angle is reduced. The actual increase in the clamping force between the jaws 5, 6 occurs in region B3.

[0060] As a result, the present design of the control surface 74 results in an overall shorter stroke of the operating element 9, an increased opening angle of the tool feature M and a reduced operating force for the operating element 9. In this way, improved user friendliness is achieved.

[0061] In contrast, the example curve K2 shows the contour of the opening angle over the stroke for a purely horizontal control surface. With a purely horizontal control surface, only about half the opening angle is achieved over the same stroke, which is a disadvantage.

[0062] The steps of the method according to the present invention for manufacturing the above-mentioned tool arrangement 3 are illustrated diagrammatically in FIGS.

[0063] In the step shown in FIG. 15, the first jaw part 5 is inserted, with the control part 53 first, into the receiving recess 72 of the housing part 7. In this case, the control part 53 is guided obliquely from above to below and proximally under the transverse web part 78 and at the same time rotated clockwise (FIG. 15). Here, the pivot bearing surface 77 and the complementary pivot bearing surface 52 come into contact with each other, thereby forming the pivot axis S. Furthermore, the pivot guide surface 79 and the complementary pivot guide surface 54 come into contact with each other. The connection thus formed between the first jaw part 5 and the housing part 7 is on the one hand pivotable about the pivot axis S and on the other hand molded radially relative to the pivot axis S, which makes it possible in particular to dispense with a separate pin, shaft or bolt connection for forming the pivot axis.

[0064] In a further step, the push-pull element 10 is inserted into the longitudinal slot 57 of the control part 53 and the control pin 14 is inserted along its axial direction through the control groove 51 and the receiving bore 102. This occurs when the first jaw part is maximally open relative to the housing part 7, which can also be referred to as the assembled position (FIG. 16). The control pin 14 is still located outside the receiving recess 72 and in the area of ​​the insertion opening E formed in the distal end of the control projection 71.

[0065] Starting from the assembled position, the first jaw part 5 is manually pivoted in a clockwise direction about the pivot axis such that the control pin 14, when appropriately positioned, passes through the insertion opening E into the receiving recess 72 and into the area of ​​the control surface 74. The control pin 14 is now guided along its axial direction between the opposing fixing surfaces 76, 76'.

[0066] In a further step (FIGS. 17, 18), the sleeve 15 is pushed axially past the push-pull element 10 and the proximal end of the housing part 7. As a result, the push-pull element 10 is fixed between the inner side (not specified in detail) of the sleeve 15 and the longitudinal guide surface 80 of the housing part 7 so as to be vertically movable. In this way, the push-pull element 10 can move in a limited vertical direction as intended between the inner side of the sleeve 15 and the longitudinal guide surface 80. The pivotability of the first jaw part 5 is positively limited on one side by the stop 56 and the complementary stop 151 of the sleeve 15. This prevents the first jaw part 5 from passing beyond the open position (FIG. 17) to the assembled position (FIG. 16) and also prevents the control pin 14 from unintentionally exiting from the receiving recess 72. In other words, the control structure 11 is essentially fixed by the sleeve 15.

[0067] In the next step (FIG. 19), the shaft 2 is guided axially over the push-pull element 10 and seated in the housing part 7. In this way, a crimp connection is formed between the housing part 7 and the shaft 2. For this purpose, the housing part 7 has a recess (e.g., FIG. 4), not specified in more detail, which interacts with a tab (without reference number) arranged at the distal end of the shaft 2. As a result of the crimp connection, the sleeve 15 is, briefly, "clamped" between the shaft 2 and the housing part 7.

[0068] In a further next step, the active part 8 of the second jaw part 6 is further fixed to the housing part 7 by a mold-fit connection in the region of the tilt axis K. As Fig. 19 makes clear, the active part 8 in this embodiment can be tilted relative to the housing part 7 by several angles about the tilt axis K.

[0069] The steps shown in FIG. 19 relate to a variant with a tool arrangement that cannot be bent relative to the shaft 2. A bendable variant is shown in FIGS. 20 and 21. In this variant, a joint tension band Z is provided. The joint tension band Z is shown in dashed lines in the covered area and interacts with the operating unit 12 and the swiveling unit 13 of the bending mechanism 12, 13 in a manner that is basically known. The joint tension band Z runs as a loop along the shaft 2 along a groove (not shown in detail) in the housing part 7. The individual pivots 131, 132, 133 of the swiveling device 13 make it possible to bend the tool arrangement 3. The arrangement shown in FIGS. 20 and 21 is preferably held together solely by the tensile force of the joint tension band Z, so that no further positive connections are required to fix the arrangement. In the region of the groove N of the housing part 7, a sleeve 15 fixes the joint tension band Z against slipping off in all directions.

Claims

1. A tool device (3) for a surgical instrument (1), comprising: the tool device (3) has a first jaw portion (5) and a second jaw portion (6), the first jaw portion (5, 6) being pivotable relative to one another about a pivot axis (S) to form an openable and closable tool mouth (M); the tool arrangement (3) comprises a control structure (11) having a control pin (14) and at least one control groove (51), the at least one control groove (51) being formed in a control portion (53) of the first jaw portion (5), the control pin (14) extending parallel to the pivot axis (S) and axially engaging through the at least one control groove (51), the control pin (14) being slidable along the control groove (51) between a proximal end position of the control pin (14) and a distal end position of the control pin (14), thus applying a torque acting about the pivot axis (S) to the first jaw portion (5) to open and close the tool port (M); the second jaw part (6) has a receiving recess (72) that at least partially receives the control part (53) of the first jaw part (5), at least one control protrusion (71) protruding inwardly from an inner wall (73) of the receiving recess (72) in the axial direction (A) of the control pin (14) and forming a control surface (74) of the control structure (11), the control pin (14) sliding along and being radially supported on the control protrusion (71) during movement between the proximal end position and the distal end position of the control pin (14).

2. 2. The tool device (3) according to claim 1, characterized in that the second jaw portion (6) has a fixing surface (76, 76') which defines the receiving recess (72) in the axial direction (A) of the control pin (14), and which positively fixes the control pin (14) against axial displacement during movement of the control pin (14) between the proximal end position and the distal end position.

3. 3. A tool arrangement (3) according to claim 1 or 2, characterized in that the second jaw part (6) has a pivot bearing surface (77) which defines the pivot axis (S) and which interacts in sliding relation with a complementary pivot bearing surface (52) of the first jaw part (5).

4. 4. The tool arrangement (3) according to claim 3, characterized in that the pivot bearing surface (77) of the second jaw part (6) is formed by the outer periphery of a transverse web part (78) extending in the axial direction (A) of the control pin (14) above the receiving recess (72).

5. 5. The tool arrangement (3) according to any one of claims 1 to 4, characterized in that the second jaw part (6) has a pivot guideway (79) curved concentrically with respect to the pivot axis (S) and in sliding interaction with a complementary pivot guideway (54) of the first jaw part.

6. 6. The tool arrangement (3) according to any one of claims 1 to 5, characterized in that a stop (151) arranged and / or formed on the second jaw part (6) positively interacts with a complementary stop (56) of the first jaw part (5) about the pivot axis (S) in an open position of the tool mouth (M).

7. 7. The tool arrangement (3) according to any one of claims 1 to 6, characterized in that the second jaw portion (6) is fixed with respect to the pivot axis (S) and the first jaw portion (5) rotates about the pivot axis (S) relative to the second jaw portion (6) during opening and closing of the tool mouth (M).

8. 8. The tool device (3) according to any one of claims 1 to 7, characterized in that the second jaw part (6) has a housing part (7) consisting of one piece and an active part (8) attached distally to the housing part (7), the housing part (7) having at least the receiving recess (72) together with the at least one control projection (71) and / or the pivot bearing surface (77).

9. The tool device (3) according to any one of claims 1 to 8, characterized in that the control groove (51) extends continuously and linearly between a proximal groove end (511) and a distal groove end (512).

10. A surgical instrument (1), comprising: A shaft (2) extending along a shaft longitudinal axis (L); A tool device (3) according to any one of claims 1 to 9, which is arranged on the distal side of the shaft (2); a gripping device (4) arranged proximally on the shaft (2) and having an operating element (9) operably connected to the tool device (3) via a push-pull element (10), the push-pull element (10) being translatable along a longitudinal movement axis (L') by operation of the operating element (9); Equipped with The control pin (14) of the tool device (3) is slidable along the control groove (51) between a proximal end position of the control pin (14) and a distal end position of the control pin (14) by longitudinal movement of the push-pull element (10), thus applying a torque acting about the pivot axis (S) to the first jaw portion (5) to open and close the tool port (M).

11. A surgical instrument (1) as described in claim 10, characterized in that the second jaw portion (6) has a longitudinal guide surface (80) extending parallel to the longitudinal movement axis (L') of the push-pull element (10), the longitudinal guide surface (80) slidably guiding a complementary longitudinal guide surface (101) of the push-pull element (10) at least temporarily during its longitudinal movement.

12. 12. The surgical instrument (1) according to claim 10 or 11, characterized in that the control surface (74) has a proximal surface portion (741) and a distal surface portion (742, 742a), the proximal surface portion and the distal surface portion being differently inclined with respect to the longitudinal movement axis (L') such that different transmission ratios are achieved between the longitudinal movement of the push-pull element (10) and the pivoting of the tool port (M) during the movement of the control pin (14) between the proximal end position and the distal end position of the control pin (14).

13. A surgical instrument (1) according to claim 12, characterized in that the proximal face (741) extends parallel and / or at least substantially parallel to the longitudinal movement axis (L').

14. A surgical instrument (1) according to claim 12 or 13, characterized in that the distal surface (742a) is curved concentrically with respect to the pivot axis (S).

15. A surgical instrument (1) according to claim 12 or 13, characterized in that the distal surface (742) is straight and tangent to an arc arranged concentrically with respect to the pivot axis (S).

16. 16. A surgical instrument (1) according to any one of claims 11 to 15, characterized in that the control pin (14) is at least temporarily held in the distal groove end (512) of the control groove (51) and rotates together with the first jaw part (5) about the pivot axis (S) upon movement of the control pin (14) towards the distal end position.

17. 2. A method for manufacturing a tool device (3) according to claim 1, comprising a step of primary moulding the second jaw part (6), wherein at least one housing part (7) of the second jaw part (6) carrying the at least one control projection (71) is provided by primary moulding.

18. 18. The method according to claim 17, comprising the step of positively joining together the first jaw part (5) and the molded housing part (7), wherein a pivot bearing surface (77) of the second jaw part (6) formed on the housing part (7) and a complementary pivot bearing surface (52) of the first jaw part (5) form the pivot axis (S), are slidable about the pivot axis (S) and are fixed to each other in a form-fitting manner radially relative to the pivot axis (S).

Images